• Server-side, zero content retention: no mailbox data is stored on our infrastructure.

• Cross-tenant, cross-domain, and cross-version support: works with Exchange 2013/2016/2019/Online, Microsoft 365, Gmail/Google Workspace, and hybrid setups.

• Flexible deployment: self-hosted or SaaS to satisfy data residency and compliance requirements.

• Enterprise-grade security: TLS 1.2, OAuth 2.0, MFA, and support for advanced environments like GCC High or data diodes.

• Scalable & performant: proven in projects involving thousands of mailboxes and millions of items, with near-real-time sync.

• For ongoing synchronization

  • Keeps all mailbox elements perfectly aligned across Exchange, Microsoft 365, Gmail, or mixed environments.

  • Reduces manual updates and support tickets, saving IT time and recurring labor costs.

  • Improves productivity by giving users consistent, always-up-to-date information.

• For one-time migrations

  • Enables parallel operation between old and new systems.

  • Minimizes downtime.

  • Lowers consulting and overtime costs, and minimizes revenue loss from outages.

  • Lowers compliance risk (GDPR, HIPAA, government standards) and potential penalties.

The result is lower total cost of ownership and a faster ROI, often within the first project or sync cycle.

“Syncing mail” may refer to one of two things:

1. Server → Client sync: Sync as a mean of getting the email items, namely the messages or calendar items, from the server to client devices.

2. Full account-to-account sync (what CB Exchange Server Sync for Gmail and Google Workspace does): two mailboxes (origin and target) are kept synchronized bidirectionally. All supported items—emails, calendars, contacts, tasks—are copied as changes occur. For more details, check this article.

You configure the Polling Interval in your dashboard. This determines how frequently the service polls for new changes and syncs them. 

PLEASE NOTE: A shorter polling interval results in faster and more precise synchronization, but if your deployment is SaaS, it will also increase traffic.

Yes, CB Exchange Server Sync for Gmail and Google Workspace supports delta sync. Only new or modified items are updated after the initial transfer, ensuring faster migrations and no duplicate data.

CB Exchange Server Sync for Gmail and Google Workspace applies conflict resolution rules based on each sync pair's configuration. You can have your sync pair as "First to second", "Second to first", or "Bidirectional", and you can then have your conflict resolution rule as "First user wins", "Second user wins" or "Don't Synchronize but log the conflict".

Yes. Gmail’s labels are mapped to Exchange folders. If you have a label within a label, that is mapped into a subfolder within a folder.

Yes, you can migrate from any supported system to any other supported system, as long as one is Microsoft Exchange or Microsoft 365. Migrating mailboxes with CB Exchange Server Sync allows you to let users work with both accounts in parallel and do the migration in iterations or batches if needed.  

Yes. We have deployed this solution in large organizations with many thousands of accounts organized in sync pairs for both migration and synchronization projects. The solution has proven to be reliable over years of continuous enterprise use, delivering stable performance and consistent results in large-scale environments.

Yes, definitely. We have a SaaS (Software as a Service) offering in both US and EU - our safe cloud is at your disposal. Check prices and conditions on our product page.

Yes. CB Exchange Server Sync can synchronize:

• Public folders
  Public folders can also be mapped to normal user mailboxes if needed, and cross-tenant or cross-domain scenarios are supported.
  

• Shared mailboxes
  The setup is similar to standard mailboxes: you specify the source and target folders in the sync configuration and assign the service account the necessary access rights. 

When a Google Meet event is created in Gmail/Google Workspace and synchronized to Exchange or Microsoft 365, CB Exchange Server Sync for Gmail and Google Workspace adds a note in the event description

AddedByCbSync MeetingName MeetingType – link to the meeting

This ensures that the Google Meet link is available and clickable for users on the Exchange/Microsoft 365 side.

CB Exchange Server Sync for Gmail and Google Workspace covers almost all mailbox content, including emails, calendar events, contacts, tasks, and attachments.  There are a few expected exclusions:

• Calendar attachments are never updated from the replica to the original on bidirectional pairs (intended behaviour).
• Exceptionally large individual items are not synchronized when their size is not supported by the destination server. For example, calendar descriptions with very large HTML bodies (e.g., tables) may lose part of the content when synchronizing from Exchange to Google. This is due to Google Calendar’s limitations in handling extensive HTML within event descriptions.
• Items that are not fully supported by one of the servers are also not synchronized, for example, recurring tasks when synchronizing with Gmail/Google Workspace. 
• Recoverable Items / Deleted Items versions are not included, as they are outside the normal mailbox scope. You can, however, configure the solution to take into account your retention policies.

In practice, these exceptions do not affect day-to-day mailbox synchronization.

You can choose between two models:

• Subscription license (per sync pair, per month or year) – best for flexibility and OPEX budgeting.
• Perpetual license (one-time purchase per sync pair) – best for long-term ownership and CAPEX budgeting.

License activation is straightforward: after installation, you request a license, and then activate it. 

For successful synchronization, it is essential to know the exact Exchange Server version you have. You can find it by:

• Asking your IT administrator or hosting provider – They can quickly confirm whether you use on-premises Exchange (e.g., 2016, 2019) or Microsoft 365 Exchange Online.

• Following Microsoft’s official instructions – Use their guide to locate and match your server’s build number with the correct version: Microsoft Support

By default, Gmail groups a message and all its replies in a conversation thread. Threads are great once you get accustomed to them, as you can see multiple related messages in a single view. Nonetheless, if you prefer to list messages separately because you are used to it in Outlook, you can turn the Conversation view off. It is simple to switch back at any time.

1. Find the option Settings on the top right (cogwheel symbol).
2. In the Quick Settings window, scroll to Email threading and select Conversation view off.

You can also add a preview pane, add a signature for your messages, or adjust the keyboard shortcuts to make them more like the ones you were used to.

You can transfer Gmail to Outlook by connecting your Gmail account using the IMAP protocol or by exporting your Gmail data to a PST file and importing it into Outlook. This works well for one-time migrations of one or few accounts in which you only need to move emails once.

For ongoing updates or bidirectional synchronization between Gmail and Microsoft Exchange or Outlook, use CB Exchange Server Sync for Gmail and Google Workspace. It continuously syncs emails, calendars, contacts, and other items between both systems—keeping everything in sync for thousands of users without manual exports or imports.

GWMMO (Google Workspace Migration for Microsoft Outlook, formerly known as GAMMO or G Suite Migration for Microsoft Outlook) is a free tool from Google that helps import emails, calendars, and contacts from Microsoft Outlook or Exchange into Google Workspace. It’s useful for one-time migrations, such as moving individual mailboxes or small groups of users to Gmail.

However, GWMMO is not built for large-scale, bidirectional, or ongoing synchronization between Exchange and Gmail.

CB Exchange Server Sync for Gmail and Google Workspace, in contrast, supports continuous, two-way synchronization between Microsoft Exchange and Google Workspace. It’s scalable to thousands of accounts, centrally managed, and designed for secure enterprise environments where both systems must stay in sync in real time.