Cool.  I just learned something new thanks to you pointing it out and the paragraph about it in the manual.

This came about after a slight power blip when I was using it and I assume Pegasus was updating one of its config files. Starting a new email is fine, I get a clean field to write into, it's only replying when it get's inserted at the top of the email.

It only occurs with one of the mail boxes so it shouldn't be a global parameter.

Does anyone have an idea which file may have been corrupted? Can it be edited or replaced?

Thanks,

Martin 

Check if this option is enabled: Tools > Outgoing Mail > Messages and replies >  For replies, place the cursor on an initial blank line > If also inserting a signature, insert it just below the blank line.

Hi Brian, thanks for the reply. No, it's not enabled. 

Have you checked the signature settings for the account?

I don't have any signatures set and there's nothing in any of them.

I'm at a loss.  The only way I know of to automatically add new content to a reply is by adding a signature.  There is the reply option of replying with a template but that creates all new message content which doesn't sound like what you are experiencing.

You mentioned that it only happens with one of the mailboxes.  I assume this means a Pegasus Mail user and is not referring to an identity.

I have two mail accounts. One for work and the other for personal communication. The only difference is that they live in different directories under C:\PMAIL\MAIL. As one is fine, I assumed that all common files must be OK, leaving those files that are specific to each mailbox as being the likely culprit. Guessing that when it occurred, something was writing to a file, I have just sent myself an email and the files that have accessed, and have a time stamp that relates to when I sent the email are:

STATE.PMJ

copymyself.PMI

copymyself.PMM

WINPMFUA.PM

YHXMARSV.PMW

YHXMARSV.PNX

I'm not sure what these are but opening with Notepad, I found "p - now the" in copymyself.PMI - not surprising as that seems to relate to my copies of emails replied to.

Actually, based on that, maybe it's accessing another file, reading it, not writing to it. would it be possible to swap files between the good and bad mailboxes? And if so, which files shouldn't be moved? 

Try reindexing first (via the folder's context menu = right click). For a classification of files see here.

Got it! It was the Custom Reply Header that had got corrupted. I deleted the errant text from it and it's working normally again.

Thanks everyone for your suggestions.