Is your mail folder (did you take a backup before upgrading), in the MAIL folder off C:\PMail e.g. C:\PMail\MAIL\your-mail-folder. Also, does the MAIL folder contain the pmail.usr file from your previous installation?

Greetings from the Great Country of TEXAS,

Well I have been using PMAIL for a very long time with little problems (very small amount).  Just downloaded the latest version 4.72 and installed it in the same folder as my previous, v4.70.  NOW PMail will not open because the identity is not valid, not found on this computer.  Have used the same settings since about 2012 with no problems.  Plus all of my email does not show nor any mail folder or boxes will not show.

 Any ideas?  Have checked the folder and all of my folders and mailboxes are there, been such a long time since having any problem cannot think straight to troubleshoot this.