Gotcha.  Here's the fix:

1. Run pconfig
2. Select Standalone Configuration (assuming that's what you want)
3. Set Home mailbox: c:\users\username\pegasus   *** No slash at the end of the path ***
4. Set New mailbox: c:\users\username\pegasus   *** No slash at the end of the path ***
5. Exit with save.

The path to my mailbox is in my user directory, but the part that was causing me all the grief was that there was a slash at the end of the Home and New mailbox paths.  So,

   c:\users\username\pegasus\

caused the problem.  Changing it to

   c:\users\username\pegasus

solved the problem.  So simple, yet so frustrating.

I run Pegasus on both a laptop (win7-64-bit) and desktop (XP-32-bit), and mirror the mail folder between the two machines.  Recently I suffered a drive failure on the desktop (XP) machine.  I installed 4.52 on both, and copied the laptop mail folder over.  The folder location is c:\users\me\pegasus on both machines. I ran pconfig to set the directories, and set both the home and new mailbox locations to c:\users\me\pegasus.  I set Asynch gateway to N.

Whenever I start Pegasus on the desktop machine, I get a pop-up window titled "Invalid new mailbox!" followed by some rambling about directory permissions and so on.  Then Pegasus opens, and everything works perfectly.  How do I get rid of this annoying message?!?

Anyone?

[quote user="stderr"]Anyone?[/quote]

 I saw that message so many times last night it really drive me nuts. I finally 'fixed" it temporarily by rerunning pconfig and setting static path to the assigned drive letter showing in the win7 win explorer thing that I'm trying to learn to use. I ended up altering an existing backup copy from my former xp notebook that was on the USB stick I was configuring. When I tried to use ~a in the path it did not work.

Apparently there is some incompatibility betweenn XP and win7 64 that I have not discovered or found any workaround for yet.  I'll be happy to share with you when I find it. In the short term try to rerun pconfig and set the path and then possibly also chek paths in pmail.ini also. After I did that things worked and all old config and paths and data and settings worked fine. I'll try same USB stick again tonight and hope it still works<G>.

This is a shot in the dark but the reference to a permissions issues to me implicates UAC (User Access Control) whenever Win7 is involved.  I don't know enough about it to say whether the ACL (Access Control List) associated with the mail folder on the Win7 laptop might be getting carried over to the mail folder on the XP desktop and playing havoc.  Is it possible that the method you are used to copy the mail folder carried the ownership and ACL information as well?  Perhaps the same thing is happening when synching?  Just a thought.