Running TB 52 portable and getting this message every time I try to reply to an email on FF Portable pages. Task manager has only 1 instance running and closing the single running app lets me reply. Tried running FF in safe mode with add-ons disabled, no change. Any ideas? Thank you
You've set Thunderbird to be your mail client but it's associated thunderbird.exe at the system level. This means that Thunderbird tries to start in local mode with a profile in APPDATA but sees another copy of Thunderbird is already running. You can manually set ThunderbirdPortable.exe as your mail client within Firefox itself. Follow the directions here: https://portableapps.com/support/firefox_portable#mailto
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