To be honest the software was created by a thid party which chagres a fortune for support. I reluctantly called them in 2 days ago and they said "hmm, we don't know why this is happening. Its your server not our software." So i cant really tell you must about how it works.

All i can say is 6 days ago invoices printed instantly, now its this issue. Nothing has changed on the server with no new software installed but as i said i did double the RAM as it was ultilising 97% of it. Now its only using 70% but this was done after the problem started in an attempt to fix the issue.

I am unsure if i am allowed under copyright to paste the query here; but the query had no issues up until 6 days ago and now its over 100 times longer to execute and on client computers (not the sql browser) can timeout. The query does run in less than 0.4 seconds on the server every time i test it with no errors.

N.B. I note about exchange but due to the low number of mailboxes i can limit exchanges grab on rscources without any issues.