> However, in the account that lost its trays (thank you for your correction of my explanation of the problem) twice, the hierarch.pm is
> still present.  It is not missing.  Please could you tell me how to re-activate it?

When the hierarch.pm file is the not available to it's open exclusive call, Pegasus Mail will build a new one in memory using the PMM/PMI files in the home mail directory as a source. On the closing it will write these to a replacement hierarch.pm file. The  hierarch.pm, when re-built by Pegasus Mail though does not contain any of the trays since they are only shown in the hierarch.pm file.  

The only way to restore the trays, other than manually, is using a backup copy of the file.

Three times in the past few months (and twice on the same account) my folders have vanished leaving, behind a long list of files in the 'Mail Folders' box.  It is some error that occurs when the account is opening.  The first time it happened I redid all the folders - made new ones.  The second time was on another account and I began redoing them, only to have them disappear again.  When this happens the words 'My Mailbox' next to the mailbox icon at the top of the list of Folders/Files disappears.  I would be most grateful if someone could tell me how to recover the folders and/or prevent this from happening again. Thank you

> Three times in the past few months (and twice on the same account) my folders have vanished leaving, behind a long list of files in the
> 'Mail Folders' box.  It is some error that occurs when the account is opening.  The first time it happened I redid all the folders -
> made new ones.  The second time was on another account and I began redoing them, only to have them disappear again.  When this happens
> the words 'My Mailbox' next to the mailbox icon at the top of the list of Folders/Files disappears.  I would be most grateful if
> someone could tell me how to recover the folders and/or prevent this from happening again. Thank you

You are not losing folders, you are losing trays that hold the folders.  This means that your hierarch.pm is being trashed for some reason (most likely your anti-virus software is grabbing the file away from Pegasus Mail).  After you fix the folders/trays as you want them I would

1.    save a copy of the hierarch.pm as hierarch.sav in the same directory. This will allow you to recover at least a known good version.

2.    tell the anti-virus software to ignore the Pegasus Mail directories.

Thank you, Thomas

I have been into my various Pegasus Mail Accounts and made copies of the hierarch.pm

However, in the account that lost its trays (thank you for your correction of my explanation of the problem) twice, the hierarch.pm is still present.  It is not missing.  Please could you tell me how to re-activate it?

 I will tell my anti-virus (NOD 32) not to meddle with my Pegasus Mail Directories.

Thelma