hello,

once a month or so, one user (out of 100) faces issues to login into one schema (out of 50 in the average) of one database (out of 100). Happens suddenly without any change to this user, schema or database.

This 'lock' disappears after a few hours, w/o any intervention. Restart of IIS (hosting the DevArt app) or PostgreSQL does not change something but reboot of the OS (Windows Server) seems to help.

If I replace the server address with some other address/DNS/IP (pointing to the same IP) then it works.

I would say 'something related to the connection string is cached on OS level, in bad state and auto-released after some hours'

Does this make any sense? What would you do to examine the issue further? 

Thx a lot in advance!

   Ekki