SuiteCRM-Upgrade-from 7.3 to 7.6.4

I installed the following upgrades 7.3.x to 7.4.3, 7.4.x to 7.5.3 and 7.5.x to 7.6.3
After upgrading, I can’t open my accounts, contacts, opportunities, prospects. I get a window wit following message:
There was an error processing your request, please try again at a later time.
If this error persists, please have your administrator disable Ajax for this module

did you follow these instructions? https://suitecrm.com/wiki/index.php/Upgrade did you run a quick repair & build after each upgrade? check your logs, apache, mysql, suitecrm, etc.

best regards

Yes - I ran a a quick repair & build after each upgrade

excellent, check your logs then

best regards

Having this issue as well. WSOD. Checked logs- now what?
“There was an error processing your request, please try again at a later time.”