Windows 10: Large IMAP4 accounts bring Windows 10 Mail App to a standstill.

Hello dear Community,

I have a question for you if anyone else has observed this behavior.
I installed Windows 10 (1903) and use the Windows 10 Mail App. Added three accounts:

• Outlook.com
• iCloud.com
• Private IMAP4

Two of the accounts (Outlook.com and private IMAP4) have very few emails in their mailboxes (less than 100 in total, across all folders).


The iCloud account, on the other hand, has several 10,000 mails distributed across many folders.



If I now activate the "Download email from any period" function for the account. Then the mail app Sync dies completely. You can no longer send mails, or the sending is not guaranteed and the sync is inconsistent.



However, if you set the function on the iCloud account to "Download email from last 3 months" or smaller. Then suddenly the sending of e-mail via this account works again. Also the sync is fast and the folders are consistent again (but only for the selected period). As far as I can tell at the moment.

I think it worked with Windows 10 (1809). But I'm not sure anymore.


Can it be that the Windows 10 Mail App with very large IMAP4 accounts has a real problem?



Many greetings
Thomas

:)

 

Large IMAP4 accounts bring Windows 10 Mail App to a standstill.

Hello dear Community,

I have a question for you if anyone else has observed this behavior.
I installed Windows 10 (1903) and use the Windows 10 Mail App. Added three accounts:

• Outlook.com
• iCloud.com
• Private IMAP4

Two of the accounts (Outlook.com and private IMAP4) have very few emails in their mailboxes (less than 100 in total, across all folders).

The iCloud account, on the other hand, has several 10,000 mails distributed across many folders.

If I now activate the "Download email from any period" function for the account. Then the mail app Sync dies completely. You can no longer send mails, or the sending is not guaranteed and the sync is inconsistent.

However, if you set the function on the iCloud account to "Download email from last 3 months" or smaller. Then suddenly the sending of e-mail via this account works again. Also the sync is fast and the folders are consistent again (but only for the selected
period). As far as I can tell at the moment.

I think it worked with Windows 10 (1809). But I'm not sure anymore.

Can it be that the Windows 10 Mail App with very large IMAP4 accounts has a real problem?

Many greetings

Thomas

 

Large IMAP4 accounts bring Windows 10 Mail App to a standstill.

Hi, Andre,

thanks for the quick feedback. The behavior is only within the Windows 10 Mail App. The same accounts e.g. under iOS Mail work fine. But also the access directly via WebApp works.

Also each further account, which is not so large, functions immediately and constantly.

A sync with the very large account takes, if it works, almost an hour.

I also tried Outlook 365 (trial version) and even there it worked the way I tested it.

I have two Windows 10 (1903) laptops. On both laptops it's the same behavior with the same accounts.

I can also try Thunderbird. However, I would like to use the Windows 10 Mail App, because it worked before the update (over 6 months).

What would be the next steps?

Many greetings

Thomas

 

Large IMAP4 accounts bring Windows 10 Mail App to a standstill.

Hi Thomas

My name is Andre Da Costa; an Independent Consultant, Windows Insider MVP and Windows & Devices for IT MVP. I'm here to help you with your problem.

This might be a current limitation of the Mail app at this time handling large accounts.

Could you confirm if this happens in Mozilla Thunderbird?

http://www.mozillamessaging.com/en-US/thunderbird/

I would also recommend you file a bug report; send me the short link so I can vote on it and bring it to the attention of the Windows engineers.

https://windows10.help/blogs/entry/54-how-to-su...

Information in the above link is sourced from a trusted Microsoft MVP blog.