Login Failed when I try with SSL/993 IMAP?

[olimits7]

Hi,

I'm using RoundCube through Plesk and for some reason when I try logging in when using IMAP SSL/993 I receive an authentication failed with "plain".  I have to change this over to 143 in the RoundCube config file and then it lets me login properly.

What could be causing this issue?

Thank you!