[imp] nearly every action results in being logged out

[Michael Ruddock]

Hello

Hope I've posted in the right place

I am using IMP H3 (4.3.9) running on Parallels Plesk.

Its been up and running without problem for about 6 months. with hundreds
of email sent and received per week.

All of a sudden the user reported that whenever they do something such as
open an email. compose an email or select an email to move it then they get
logged out.

Has anyone experienced this before? Anyone got a solution?

Thanks in advance

Cheers