Notification Rules. Error while editing notification template

Notification Rules. Error while editing notification template

Service Desk Plus. Version: 12.0 Build 12001

When I try to click on the Customize template links (/NotificationContent.do?notifType=RequesterAck_E-Mail), I first get a "NTLM Failed Redirecting To Login Page.." message for a short time, and then give an error "Sorry an error has occurred".
Ok. To avoid problems with ntlm, I log in as a local user, not a domain one. But I get exactly the same result.
And sometimes the system still lets you edit the template. But very rarely.
Updating the system is not possible, since there are no plans to move away from ntlm - the system is local and the user authorization method suits us absolutely. No one will definitely deploy another system for this. And as I said, when you log in as a local user, the same result. I suppose the problem is somewhere in the database, just like with the previous problem of importing users from AD.
But how to solve it?
Can you help me?

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