This sounds like you are not actually sending using the studiocerebral.com outgoing smtp server. It sounds like you are using the audiolabsgroup.com smtp server.

Check Account Settings: Right click on the mail account name in Folder Pane and select 'Settings' In left pane, click on 'Outgoing server (SMTP)' You should see your outgoing servers listed.

• Select smtp for studiocerebral.com and do the following:
• click on 'Edit'

'Description' : this field is really for your use to help identify which server is which.

• Type something to help id the different accounts.

Eg: Personal, Business, or first part of email address.

• 'User Name' = full email address of mail account which will use it.
• click on OK

If the studiocerebral.com is nt listed as an smtp server you will need to use the 'Add' button to create one.

Then make sure outgoing server is correctly used by the mail account. Select the studiocerebral.com mail account name in left pane. On right side near bottom - Outgoing server(SMTP)

• click on Drop down and make sure you select the correct SMTP server for that mail account.
• Click on OK

I've included a couple of images to help show where I'm talking about. Obviously my details wil be different, but the process is the same.

All of my accounts use the GODADDY server, whose SMTP is the same across the board (smtpout.secureserver.net) - and I don't believe GODADDY allows us change SMTP names. What is strange is that out of 250 accounts, this is the only one that does it. I am beginning to suspect the DB is corrupted, and there is no DB tool built into Tbird. And that means I may need to delete the account, reboot, and enter that account as new again.

It would seem that you have not read the information correctly or are completely confused. You just need to use the correct smtp server, nothing so dramatic about deleting accounts.

So lets start again. If you have 250 mail accounts then each one will have it's own email address. Each email address might use the same basic smtp server settings if you have all of those domains with eg; godaddy, but it will have it's own UserName = email address and it should have it's own password. This makes it unique. So ideally you should have one smtp server per account. Whilst mail accounts can be set up to use other smtp server settings, it is not always satisfactory; this is clearly occuring in this particular case.

You are currently sending out using the wrong smtp server. The studiocerebral.com is using the audiolabsgroup.com smtp server. This has nothing to do with the details in the 'FROM' when sending the email.

• Right click on the studiocerebral.com mail account name in Folder Pane and select 'Settings' In left pane.
• click on 'Outgoing server (SMTP)'

You should see a list of all your outgoing smtp servers.

• Select each one in turn, locate the one which has UserName = the studiocerebral.com email address for 'mark'.
• Click on 'Edit' button
• In Description field type something useful so you can identify the correct outgoing server such as 'Studio-Mark' - something to help you identify that specific smtp server from all the others.
• click on OK

If you cannot find any outgoing smtp servers that have User Name = 'mark' @ ' 'studiocerebral.com', then you need to add one.

• click on 'Add'
• Enter all details making sure you put 'Studio-Mark' in the description field.
• click on OK

Then make sure that outgoing server is correctly used by the 'mark' @ ' 'studiocerebral.com' mail account.

• Select the 'mark' @ ' 'studiocerebral.com' mail account name in left pane.
• On right side near bottom - Outgoing server(SMTP)
• click on Drop down and make sure you select the correct SMTP server for that mail account. It will say eg: 'Studio-Mark'.
• Click on OK

Okay. Did that. Renamed ALL the SMTP Identities and servers to the coinciding domain. Sent myself a test message. Did this to both studiocerebral.com and audiolabsgroup.com and all the others. Did a test. Sent a test email to mark@studiocerebral.com. Got it. Hit reply. It still sends to curator@audiolabsgroup.com. Pops up in the TO field curator@audiolabsgroup.com.

My only thought is that things are screwed up at the GoDaddy level, and that I need to delete and recreate both of those email domains (POP). I appreciate your help.

When you click reply, what shows in the from box in the compose window?

Will have to report this when it does it again, but thanks!