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Fastest way to upload messages to EWS account?

Michail Pappas
Michail Pappas

In our organization we have moved from an on-premise mail server to M365. We've also added our new EWS-based accounts to Thunderbird. Since there are a large number of users with a significant amount of older mails they want to have access to, they have been asking how they could upload them to EWS now.

From the looks of it, using TB one can either drag and drop messages from the local folders to EWS. Would message copy/move from the local folders be faster if the EWS account was setup over IMAP, instead of over EWS? If so, we could setup another account corresponding to the same EWS identity, but over IMAP, just for the purposes of transferring messages faster.

Thanks in advance for any information provided.

In our organization we have moved from an on-premise mail server to M365. We've also added our new EWS-based accounts to Thunderbird. Since there are a large number of users with a significant amount of older mails they want to have access to, they have been asking how they could upload them to EWS now. From the looks of it, using TB one can either drag and drop messages from the local folders to EWS. Would message copy/move from the local folders be faster if the EWS account was setup over IMAP, instead of over EWS? If so, we could setup another account corresponding to the same EWS identity, but over IMAP, just for the purposes of transferring messages faster. Thanks in advance for any information provided.

All Replies (4)

Wayne Mery
Wayne Mery
  • Moderator
  • Top 10 Contributor

Drag and drop adds a layer that imposes a performance penalty.

Using Tools > Filters will be faster. You can run a filter against a specific folder.

Michail Pappas
Michail Pappas Nkolo motuna

I've also tried marking the messages, right-clicking, selecting move and then the relevant destination EWS folder. Is this the same as dragging and dropping or is it the same as using tools -> filters?

Matt
Matt
  • Top 25 Contributor

Have you considered using the tools provided by Microsoft for migration? https://learn.microsoft.com/en-us/exchange/mailbox-migration/mailbox-migration

Did your organization perhaps drop the ball when it came to migration. It appears to be a component that many businesses do poorly.

Michail Pappas
Michail Pappas Nkolo motuna

Complex migration, involving many DNS subzones, each with its own mail server (and each mail server with its own serving protocol, mostly POP3 meaning everything on a client's rig). Migration planning could definitely be better, but it is what it is. We've been trying to get our part of the job done properly (handling a specific region) and thankfully, the project went well, after a lot of documentation produced, user grunts and heads bashed. We did/do run into some issues on Thunderbird and try to report them promptly, with any luck these will be ironed out.

I've opened this thread because there's the occasional really large mailbox (> 100Gbyte) and since M365 offers a special archiving feature (and there's a bug there since TB does not display it, but no time to report) migrating to EWS is a nice way to keep access wherever the user is. Transfer is extremely slow though, hence for our question here, trying to find the fastest means to get the job done.

Tuna motuna

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