My system administrator told me to delete this app, because it's killing trafic:)
I am not sure why your sysadmin said that. Aquamail is not using more traffic then any other typical e-mail client (e.g. Thunderbird).
About draft folder, it's mapped to draft. It's always empty. Don't know why app is trying to get something, while there is nothing to get. Screen attached.
OK, so it is configured as it should be.
You have it configured to sync (it may have been done automatically by Aquamail). And that's the right way: it allows you to preserve the draft(s) of the messages on the server, so that you can continue writing your message later - and not just from Aquamail but also from any other client that you may have connected to this account, or the webmail interface if that is configured so.
I am not sure why there is an error. I've seen some people reporting recently some "jitter" between different languages by some big mail providers, where the language was switching sporadically from the local one to English, causing some problems with the "special purpose" mail folders. From the error your posted, it doesn't seem to be the case, - but it is not completely clear.
Have you sent the debug log to the developer?
Can't use scheduled imap, I need mails on time. Will try with 5 min schedule.
This statement is very confusing. I suspect something may have been lost in translation from Lithuanian. So, could you please clarify a few things:
1. Are you using EWS or IMAP type of connection (Aquamail account)?
2. Do you have IMAP connectivity available at your mail server?
3. If yes, does the server's IMAP support PUSH?
If the answer for #2 and #3 is "yes", and if you indeed need quick notification about incoming messages, - you can configure your account as IMAP, and enable PUSH. (You cannot convert a EWS accountinto an IMAP account in Aquamail, so, you'll have to create a new account, choosing "IMAP", and then delete the EWS account. But you will loose some EWS-based functionality that way.)
P.S. I find that most people (90% if not 95%) do not really need immediate notifications for the e-mail messages, and 5-minutes frequency is more than sufficient.
On the opposite side, just recently (a few years ago), one of the top managers of IT group of my employer (where over 50 000 people within the organization rely on e-mail communication, internal and external) stated that a 1-hour delay of e-mail delivery inside the organization is not a problem. (And for the record, - I strongly disagree with that.

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