I am unclear on this. Are you saying that when you send messages from alebow, the recipient sees the message as from mlebow? What is 'write mode'? Please provide more specifics. Thank you.

My files on alebow are corrupted; they say that they are sent from mlebow and they give the reply to address instead of what should be the from address. The to address is OK as it is the alebow address. But the send function is always at the top of the file.

In addition I can't send email from the alebow files even if the problem above is fixed.

Is it that you have one account or two on THunderbird? Could you show screenshots of incoming server settings and also the SMTP server settings? I'm having trouble grasping the extent of the issue. Thank you.

On this forum I found about the addon FolderFlags that seemed to solve my problems. But when I downloaded it and tried to access it using tools, view and toolbars I could not get it to work. Nevertheless I found that my problems were were solved. I don't know how but I now have TB 115.6.1

If you use the hamburger menu, click the 'addons' entry and there is a gearwheel showing. click that and an option is to install from a file. If you use the menu bar, it is tools>addons and then the gearwheel