Yes I copy them back then reindex the folder by deleting index.xml
The mobile devices are all Samsung Galaxy 10 using the MS Outlook app.
I am in the process of getting everyone to use the webmail app instead in the phone and PC.

I am getting an error when trying to attach a large 40MB file in webmail. The message I get is 'The page was not displayed because the request entity is too large'. I can send a 25MB file but not much larger. I want to limit attachment size to 100MB I set the maxRequestLength="100240" in web.config ...

Not supporting Outlook has become a problem for some of my users. The issue has become worse and Outlook is slower than ever before. Some users have 250K emails in their mailbox and for these users Outlook has become unusable. I do not have XLIST enabled. Switching users to MAPI has also not worked ...

This is still a problem that I need to resolve. Users are asking for more access to old emails. That would put many clients with over 250k emails. Is it time to look at other email server software. Doesn't seem ME can handle this. Any suggestions?

Now I am getting this error from a user using Outlook. Yesterday I did a repair on Outlook and changed to MAPI from IMAP. It worked all day, then today the error returned.
Also the article you recommended returns 404 error.

I do use Magicspam. Think maybe that could be doing it?

I personally use Thunderbird client with 5 mailboxes and I can replicate this error my just doing 'Get Messages' or starting the program. I turned on the high level debug and see the error happening, but still don't know why. I do not want to pay extra for a support ticket when I pay every year for ...

Haven't seen this issue again. Maybe if I do I will raise a support ticket.

Don't want to pay for a support ticket for a bug report.

What does 'Couldn't decrypt, error 80090330' mean? A web search found no explanations or resolutions
This happens a lot in the IMAP debug logs. Maybe I should just ignore these errors? I would still like to have an explanation.

I would consider downgrading if others had fixed these issues by downgrading.

Was seen on webmail as well.

Yes 10.35. Now I see 10.36 available, but I may wait on that. I don't see any IMAP issues fixed in the release notes.

Here's another IMAP issue I just installed Outlook on a client. They have an existing user account with many emails. Only the Inbox emails appeared. None of the other folders have any email in them. I made sure they were subscribed to these folders and selected in the send/receive option. I even tri...

The largest mailbox disk usage size is 26GB with an inbox size of 35K messages and 21K sent messages, The average of each other mailboxes is between 4K and 6K messages. I already delete all messages older than 180 days and they are ok with that, but not a shorter period. If ME can't handle this then...