Email Backup Software for Windows

Safely back up your emails from the cloud to your hard drive (and restore them later if necessary).

Email is one of the most valuable digital information resources a company owns. It can contain all sorts of information, including plenty of sensitive data: business agreements, company secrets, personal information, bank statements, tax returns, medical records… The list is endless.

Arguably, some of this should never be sent by email but, nevertheless, it is. Which means it’s precious and must be safeguarded. It needs to be backed up.

Statistic: Number of sent and received e-mails per day worldwide from 2017 to 2025 (in billions) | Statista

What to look for?

The best email backup software needs to:

  1. Securely save your company (or customer) email to a backup medium.
  2. Do so without any data loss (to visible or hidden data).
  3. Enable you to access or restore the backup.

Data security and integrity are crucial, not only for peace of mind (your own and your customers’) but also for regulatory compliance. Good software can make the difference between a secure and complete email backup, and a botched job that results in non-compliance and potential government fines.

An award-winning tool

Aid4Mail is an award-winning email-processing tool that can securely back up all your mail. Based on years of expertise in email processing, the first version of Aid4Mail appeared in 2005. By 2016, it had won a European IT and Software Excellence award and is now an industry leader in email recovery, collection and conversion.

There are three editions of Aid4Mail:

  1. Aid4Mail Converter enables you to back up unlimited company or customer mail.
  2. Aid4Mail Investigator adds advanced filtering so you back up only what you need.
  3. Aid4Mail Enterprise adds the ability to restore backups to cloud-based email services. It also enables full automation and can run from a server.

Aid4Mail comes with full documentation, tutorials, knowledge-base articles and access to our award-winning Helpdesk.

Try Aid4Mail for free – no commitment

The best way to discover Aid4Mail’s capabilities is to try it out. Download the free trial version now. There’s no time limit and no obligations. Or start backing up your email immediately using our low-cost two-week Converter license.

Download free trialGo to Pricing

Security first and foremost


Aid4Mail is an on-premises tool which is inherently safer than an online solution. All mail is processed on your own computers or servers. Nothing is sent to our servers. You have full control of your own data.

Secure connections to cloud accounts

Access to cloud-based accounts always uses the highest-level security protocols available, by default. Google Workspace (Gmail) and Outlook accounts are accessed through native APIs. Connection to IMAP accounts is through encrypted protocols, notably OAuth 2.0 when available.

Data integrity

Nobody wants their backup to be altered or incomplete. Maintaining its integrity is critical. It has also become a legal obligation as many jurisdictions expand their data-retention regulations.

To back up mail, it usually needs to be converted to an appropriate format. And Aid4Mail is the most accurate email conversion software on the market. It is fully Unicode-compatible and preserves more crucial data, visible and hidden, after conversion than any of its competitors (including the native import/export features of most mail apps). No matter the format you choose for your email backup, you know it will remain intact.

Here’s an example of how much better Aid4Mail performs with visible email data. Notice that it has no problem with the accented characters in the first line, the embedded image or the Chinese attachment name at the bottom.

Back up virtually any mail format

Aid4Mail supports most email formats in use today:

  • Microsoft Exchange Server (via MAPI)
  • Cloud-based email services:
    • Google Workspace, Gmail (via Gmail API)
    • Microsoft 365 / Office 365,, Hotmail (via MS Graph API)
    • IMAP accounts (including most webmail services like GoDaddy, Yahoo! Mail, Zoho, AOL and more…)
  • Mail clients:
    • Microsoft Outlook
    • Mozilla Thunderbird and SeaMonkey
    • Apple Mail
  • Mail stores and mailbox files (even when disconnected from their mail app):
    • Outlook OST, PST and OLM
    • Mbox
    • Google Takeout
  • Message files (even when disconnected from their mail app):
    • Outlook MSG
    • EML
    • Apple EMLX
    • Maildir

In addition, Aid4Mail Enterprise can migrate from email archive formats and even reorganize them by user, date or whatever criteria you choose:

  • Google Vault
  • Mimecast
  • Proofpoint

Aid4Mail set up to migrate Mimecast, Proofpoint and Google Vault archives.

Try Aid4Mail for free without any commitment. Or start your email backup project right away with an Aid4Mail license.

Download free trialGo to Pricing

Speed and efficiency

Creating backups of email data can be time consuming. Most companies have millions of emails, spanning years and usually occupying several terabytes of storage. Backing it all up can be a headache. Aid4Mail reduces the pain, saving you time and money.

Optimized for speed

First of all, Aid4Mail has been optimized for speed and stability. In tests with locally-stored files, Aid4Mail performed 6 to 10 times faster than its competitors. This means that a huge backup that might take a week to create with a competing product, would require just one day with Aid4Mail.

A customer recently told us about their Proofpoint archive migration. The archive was 985 GB and contained almost 3.3 million emails from different users, all mixed together. They used Aid4Mail Enterprise to migrate the archive to individual EML files and group them by account holder. All in less than 7.5 hours at a rate of 122.7 emails per second!

You don’t have to be present

Aid4Mail is very stable and can work through terabytes of data without user intervention. Even if a large project takes hours, days or even weeks to complete.

If Aid4Mail encounters a problem, it tries again whenever possible. If the problem persists, Aid4Mail is usually able to move on. This enables you to launch a backup project and then work on something else while Aid4Mail’s running in the background.

Concurrent processing

With Aid4Mail Investigator and Aid4Mail Enterprise, you can run multiple backup tasks simultaneously, taking full advantage of your computer’s hardware and saving even more time.

For example, back up mail from five different sources simultaneously. Or back up different date ranges from a single source at the same time (using Aid4Mail’s date filter). Launch all the tasks together and let them run, unattended.

Multiple archiving tasks processing simultaneously in Aid4Mail.


Although Aid4Mail can be run as many times as you want, backup tasks are typically launched manually. If you need to back up on a regular schedule, you really need an automated solution. Aid4Mail Enterprise accomplishes this.

Aid4Mail Enterprise ships with a console (CLI) version of the application, enabling full automation. You can run it from a batch script on a set schedule, or from your own software, integrated with other tools. Set it up once and let it run every day, unattended.

Choose exactly what to back up

Folder filtering

If you need to back up in stages, Aid4Mail lets you target specific folders. Available in all editions, this allows you to prioritize certain emails over others. For example, first backup up folders related to customer contracts, leaving the Christmas party folder for later.

Aid4Mail's folder filter.

Sophisticated filters

Only back up exactly what you need. Aid4Mail Investigator and Aid4Mail Enterprise include powerful filters to optimize and organize your backups and avoid the long-term storage of clutter.

For example, eliminate duplicate emails, unpurged mail and non-personal messages like circulars and adverts. Use date, address and keyword filters to back up your mail in stages. Or reorganize them to suit your requirements.

The filtering possibilities are almost limitless. Use powerful features like proximity searching, wildcards and regular expressions (regex) along with Boolean operators to create sophisticated search terms. You can even create your own Python scripts for full customization.

Native filtering

Aid4Mail Investigator and Aid4Mail Enterprise also offer native filtering–the ability to send search queries to the mail server itself. This is available with all cloud-based accounts and PST files.

The advantage of native filtering is that only emails matching the filter criteria are downloaded from the server. This speeds up the backup process considerably and can avoid bottlenecks like server quotas and bandwidth limitations.

Native filtering and sophisticated item filtering in Aid4Mail.

Incremental processing

Another way to back up in stages is using incremental processing, offered in all editions. When turned on, Aid4Mail keeps a list of all the emails it backs up. Then, when the same source mail is processed again, only new emails that arrived since last time are backed up. This is also useful if processing needs to be resumed following a lost connection, server error, or other temporary problem that caused Aid4Mail to stop.

Try Aid4Mail for free without any commitment. Or start your email backup project right away with an Aid4Mail license.

Download free trialGo to Pricing

Back up mail without imprisoning it

Many backup solutions store your mail in proprietary formats. And often make it quite difficult to move away from their system. We don’t believe in locking you in like that so Aid4Mail takes a different approach.

Back up in non-proprietary formats

Aid4Mail offers a range of non-proprietary file formats to back up your mail, as well as Outlook formats that, although proprietary, are so commonly used they’re widely supported. You’re free to choose what suits your needs best. Save to:

  • Email stores and mailboxes, like Outlook PST and mbox.
  • Individual email message formats, like EML and MSG.

Aid4Mail also makes it easy to back up email to multiple formats when necessary.

Liberate proprietary backups!

Aid4Mail Enterprise can free your mail from locked-in proprietary backups by converting them to non-proprietary ones. It can even reorganize them when they’re delivered in a mess (more common than you’d think)!

For example, exported Mimecast archives are often delivered in huge packages. They contain mail belonging to many different users, all mixed together. To our knowledge, Aid4Mail is the only product on the market that can reorganize these archives by user account. After migration with Aid4Mail, each user would have their own PST file, for example, containing only their mail.

Choose how to back up journaled emails

If emails have been journaled, Aid4Mail offers two options:

  1. Leave them that way and back them up as journaled emails.
  2. Restore them to their original pre-journaled states.

Restoring a journaled email involves removing its journaling envelope. However, the envelope may contain important metadata that you don’t want to lose. Aid4Mail is able to save the metadata by injecting it back into the email header. The email is then restored without data loss.

Easy access to backed-up mail

Choose the best viewer for your needs

Email backup solutions that use proprietary file formats often include their own viewer–usually the only way to access your backups and often limited in functionality. They are promoted as a feature but, in reality, are a necessary component in locking you into their system. Again, Aid4Mail takes the opposite approach.

As Aid4Mail stores your backups in non-proprietary or widely-supported formats, you are free to choose the most suitable application to view them in. For example, access PST files in Outlook, import mbox backups into Thunderbird and view EML files in any number of email apps. Choose what works best for you.

Reconvert backups when necessary

For example, if you decided to back up mail in mbox files but, later, would like to view them (or a subset of them) in Outlook, that’s no problem. Although Outlook cannot import mbox files, Aid4Mail can reconvert between most of its email mailbox and message formats. And without losing the original (mbox in this example).

Reinstate mail into a live system

Reconverting mail backups also offers the possibility of restoring mail back into the live system where it first started. In our example, above, converting the mbox backup to PST would allow it to be brought back into an Outlook-based system.

In addition to converting between backup formats, Aid4Mail Enterprise can also convert directly to certain email apps and services. Notably to an Outlook profile / Exchange Server, Office 365, Google Workspace / Gmail account or IMAP account.

Aid4Mail reinstating multiple PST archives to their respective Gmail accounts.

Find specific emails quickly

Email backups can be large. It’s all very well being able to access the backups in your app of choice. But sometimes the problem is which emails to access. How do you find the specific ones you’re looking for? Aid4Mail offers some clever solutions.

Custom folder structures

One of the simplest ways to facilitate finding specific emails is by storing them in a logical folder structure. Like all email backup solutions, Aid4Mail can maintain the original folder structure. But what if the original structure wasn’t very good?

Aid4Mail enables you to completely reorganize and customize the folder structure. For example, create a folder structure based on the year, month and day emails were sent. Or who they were sent to/from, their subject, their status (sent/received), the project they were part of, or a combination of all of these… The options are almost endless.

Custom filenames

Similarly, a clever choice of filenames makes a huge difference when looking for specific emails. The naming of mailbox files is usually straightforward. However, individual message files are numerous and problems can arise when they lack thoughtful names.

Aid4Mail can apply the same customization, that was used for the folder structure, to filenames. In fact the two work together in tandem. Used judiciously, this produces a folder-file naming convention that simplifies email retrieval.

For example, the email previously stored at:

XYZ project mail\tyx7e8sfas.eml

becomes much easier to find when the folder structure and filename are set to:

Fookes Software\XYZ project\Mail received\2020\John Doe - 2020-06-21.eml

Search directly for emails

Sometimes a great folder-file naming convention is still not enough. You need to be able to locate specific emails based on information inside them. Or, worse, inside their attachments. This is where Aid4Mail Investigator and Aid4Mail Enterprise’s sophisticated search engine comes into play again.

The same powerful search features, that enabled you to choose which emails to back up, can also be used to locate specific emails in the archive. Used in conjunction with the reconversion feature, they enable you to create a subset of your backup, in your format of choice, that contains the required emails and can easily be viewed in your preferred application.

A complex search query, using a regular expression, in Aid4Mail.

Try Aid4Mail for free, without any commitment. Or start your email backup project right away with an Aid4Mail license.

Download free trialGo to Pricing


Why should you back up email?

The main reason is so you have control of your email. You have a copy of it if your service provider goes out of business or accidentally loses your data. Your email isn’t so easily hacked when most of it is stored on your own servers. And it can’t be held for ransom by identity thieves if you have a copy stored offline.

Backing up email also reduces the amount of server storage needed from your provider and, subsequently, the cost. Finally, but very importantly, it protects you from onerous fines or lawsuits that can result from ignoring data retention regulations.

Can Aid4Mail be used for IMAP backup and restore?

Yes. All editions of Aid4Mail function as IMAP email backup software as they are able to backup IMAP email locally. However, only Aid4Mail Enterprise can restore backed-up mail to an IMAP server, making it the best all-round IMAP backup tool.

Can Aid4Mail create GoDaddy email backups?

Yes. Aid4Mail accesses GodDaddy accounts through IMAP so all editions can back them up. Aid4Mail Enterprise can also restore them.

Can Aid4Mail backup Gmail emails to a hard drive?

Yes. All editions of Aid4Mail can back up Gmail accounts, accessing them directly through the Gmail API or through IMAP. All editions can also migrate Google Takeout backups. Additionally, Aid4Mail Enterprise can migrate Google Vault archives as well as restore backed-up mail to a Gmail account.

Can Aid4Mail be used as a Microsoft 365 (Office 365) or email backup tool?

Yes, all editions of Aid4Mail can download cloud-based Outlook emails to hard drive. However, only Aid4Mail Enterprise can restore mail to these services.

Can Aid4Mail be used for Thunderbird backup and restore?

Yes, all editions of Aid4Mail support Thunderbird for both backup and restore.

What makes Aid4Mail so good?

We have been developing software since 1990. Our first email tool was launched in 1999 and Aid4Mail followed in 2005. Our experience in processing email data spans over two decades.

All core functionality in Aid4Mail is developed in-house. Key features are tightly integrated and optimized for speed. We are in full control of our code, including major components like email parsing and conversion, the filter engine and its search syntax, MAPI access to Outlook accounts, and even the IMAP protocol used to connect to services like Yahoo! Mail and AOL.

Important clients around the world rely on our software. These include US government and law enforcement agencies, top law firms, national libraries, prestigious universities, major banks, and international NGOs. Currently, half of Fortune 50 companies are Aid4Mail customers.

Aid4Mail is Swiss Made and meets the high-quality standards that Switzerland is famous for.

Where can I get Aid4Mail?

You can download a free trial of Aid4Mail from our downloads page. Licenses can be purchased from our online store.

Where can I get help?

Aid4Mail is installed with a very comprehensive, context-sensitive user guide. Just press the F1 key while using Aid4Mail to open it. Alternatively, you can download the PDF version.

There’s also a whole range of tutorials and knowledge base articles on our website. If you’re still stuck, contact our award-winning Helpdesk.

About Fookes Software

Fookes Software Ltd
La Petite Fin 27
1637 Charmey (en Gruyère)

For over 25 years we have been developing award-winning tools and productivity software. We also have more than 20 years of expertise in the field of email processing and analysis.

Our clients include Fortune 500 companies, government agencies, law firms, universities, and professionals specializing in e-discovery and forensics from around the world.

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