After playing around with all the settings in Outlook, there is a settingcheckbox in Define SendReceive Groups -- Edit -- Receive mail items.

The problem is that in the status box, it shows synchronizing subscribed folders and usually shows about 2 minutes.

Sometimes it starts over and sometimes it goes up to 8 minutes.

Im pretty familiar with the way Outlook and Gmail work and have had problems with it in the past as many people do (as evidenced by all the problem posts found on Google).

Ive set the sync interval to 1 minute or 5 minutes or 30 minutes.

Once the sync completes, outgoing mail sends and incoming mail comes in, but then it will sync again and no mail transfers until its done.

His old laptop did something similar with outgoing email taking a while to initiate sending or for new email to get fetched and they thought a new computer would fix it.

Outlook 360 Running Slow Plus This Problematic

The weird thing is that another computer being used in the office has another 2 gmail accounts plus this problematic account and it seems to be able to send and fetch WHILE the sync is in progress.

While its a little slow, its much more responsive than the main user of the problematic email account.

This other computer has Outlook 2016 and not the newer 2019 v1906 thats on the new computer, but the old laptop of problematic user also had Outlook 2016 and had problems.

Ive gone through selective folder synching and only synchingsubscribing to the Inbox.

Ive set Gmail to only allow synching of 1000 items in each folder.

Ive turned off Starred, Snoozed and Important folders for IMAP.

Outlook 360 Running Slow Update Unread Count

Ive set it not to update unread count and several other possible tweaks.

Internet speed it good - cable modem at about 100Mbps down and 17Mbps up.

The mailbox used to be 11GB and we removed older emails so its only about 3.6GB now.

There are quite a few folders (maybe 30-40) but per above, this account works OK on another computer and all the settings are identical with the exception that Outlook is 2016 and not 2019.

Most of the time when I have clients trying to use Outlook and Gmail, I just move the client to something else like Office 365 Exchange, but this client doesnt want to useget their own domain name and wants to stay with the gmail.com accounts.

I know Outlook and IMAP Gmail isnt the best matched pair.

Thats why I tell clients to either use the gmail web interface or switch to something else.

These arent options at this point so Im hoping there is a magic bullet that will make things run more smoothly.

In general, with Outlook and Microsoft Exchange via Office 365, once a sync is done, syncs are very low overhead.

I dont know why Gmail has so much of a time overhead to sync.

One thought I just had is that maybe if more than one Outlook is synching with the account, that can cause it to be slow.

Im not sure if the second computer was running Outlook when I tested, but perhaps the first Outlook that connects has better speed and the second and subsequent Outlooks connects to the same account get slow.

Ive checked about 20-30 different links via Google searches and implemented all the fixes so Im looking for any obscure off the wall fixes and not the generic fixes that are plastered all over the place out there.

Ironically iOS devices seem to work fine synching with the account.

Outlook 360 For Mac Running Slow