Since I moved to Office 365 on Windows 11, Outlook has regularly been running out of resources - usually at least once a day, which is a pain.



Even when Outlook is closed, when I am working on the PC it eventually comes up with the "out of resources" message. I can fix it by restarting the PC.

It doesn't seem to be a RAM issue - when it happens I usually have about 7GB free out of a total of 16GB, and I have over 500GB free on the SSD.

There are 4 accounts in Outook, two very small, one not so large and the 4th one is quite big. All are IMAP.

This all worked fine on the previous PC - Office 2003 (I know !) and Windows 7, with similar-sized Outlook files and only 8GB RAM.

Also my wife has a very similar installation on her Windows 11 PC which has only 8GB RAM. She has no problems at all.

Any ideas as to the cause, a fix, or further diagnosis would be most welcome.

Thanks

Martin

Further information . . .
1. There are no Outlook add-ins
2. I have increased to PageFile size from 4GB to 8GB - I'll see what that does
3. There's something really odd about my .ost files
I think that this goes back to Outlook 365 problems when the whole system was new and Microsoft support played with it for ages to get my mail accounts working. I'm not sure exactly what they did, but they did create some new .ost files.
Anyway, in the Outlook folder I have quite a few .ost files, 8 of which have today's date under "Date modified" so I guess they're all in use - but there are only only 4 mail accounts.

They are as follows:

<my name> - Outlook New.ost 1,700MB
<my email address>.<this PC's name>.ost 3,100MB

<wife's name> - Outlook New.ost 800MB
<wife's email address>.ost 1,700MB

<my gmail address> - Outlook New.ost 130MB
<mygmail address>.ost 160MB

<my hotmail address> - Outlook New.ost 150MB
<myhotmail address>.ost 230MB

This looks to me like an unholy mess ! Any ideas how I can start to sort it all out ?

Thanks !

Solved !
When MS "fixed" my Outlook installation they created a second profile - both were active.
I've now deleted the old profile and all seems well - so far at least.