Since the -roam switch is necessary for me to access my mail on different computers having different available drive letters for USB, it is now clear to me that the easiest solution (for me) is for the entire PMAIL folder to reside in the root directory of the encrypted volume. Thank you all for your comments, which will certainly be useful to those not needing the -roam switch, or for those having more experience and understanding of the processes than me.

Due to the nature of my business, I installed Pmail on a USB drive so that I can read and write email wherever I may be working. In order to protect my mail, the Pmail folder is in the root directory of an encrypted Truecrypt file, which acts like a disk drive. In order to save space in my encrypted file, can I place the Mail folder in a location separate from the Programs folder, or do they both need to be in the Pmail folder?

The -ROAM switch requires that both the executable files and the mailbox directories be accessible from the same drive letter.

 Excerpt from the Command line options topic of the help file:

-ROAM...You must not use this switch if Pegasus Mail and your mailbox directories cannot be accessed using the same drive letter....

There might be another option though.  You should be able to store messages in a directory off of the Truecrypt drive and access them using the  "Add mailbox to list" folder option.  I have not tried this but it might be worth testing. 

If you wish to pursue it, here's how.  Create a directory on the USB drive that you want to use as the added mailbox and then add that directory to the Pegasus Mail folder list as an added mailbox.  To do this, open the Folder window and with it active, select the Folders pull down menu then select "Add mailbox to list...".  In the "Add a mailbox to your folder list" window select "Directory path", browse to the created directory, assign the added mailbox a name then click OK.  You will see it appear at the bottom of the folder list.  An added mailbox behaves just like any other mailbox folder so you can copying some messages to it for the testing phase.  Do some restarts and connections of the USB drive to other machines.  Note:  I believe you will need to re-add the directory as a mailbox each time the drive letter of the USB drive changes.  Once all is well then move messages or folders to it instead of copy (I prefer to copy, verify, then delete the originals rather than move).  Be sure to do the copies and/or moves from within Pegasus Mail.  Also, be prudent and do a backup before testing.

[quote user="dlbayne"]

Due to the nature of my business, I installed Pmail on a USB drive so that I can read and write email wherever I may be working. In order to protect my mail, the Pmail folder is in the root directory of an encrypted Truecrypt file, which acts like a disk drive. In order to save space in my encrypted file, can I place the Mail folder in a location separate from the Programs folder, or do they both need to be in the Pmail folder?

[/quote]

Keep in mind that Pegasus Mail must have read/write permissions plus no files in \mail or contents below may be marked read only or encrypted during operation from time started thru the time of proper closure and all drive writes have ceased.

Use of the 16bit PCONFIG to set paths may also be problematic if you are using 64bit OS on the host machine with the USB drive 32bit machines would not be a problem since those can run PCONFIG without aid of another application to enable using 16bit code like DosBox.