This problem started earlier this year after a PortableApps update. I didn't track which one, I just ignored it and worked around it thinking it would be fixed in the next update. Nope.
When having PortableApps start Firefox and Thunderbird automatically, and then clicking on a link from Thunderbird, PortableApps tries to open another Firefox and then gives the dreaded "Another instance of Firefox is already running" error box. The only times this occurs are when both are set to start automatically. If only one or the other is set to start automatically, and then the other is started manually, everything works. If only Thunderbird is set to autostart, then clinking on a link starts the other and works. if neither are set to start, and are started manually, it works. I even registered FirefoxPortable.exe with windows as the browser to use as posted a few other places but it had no effect.
The ONLY time I have the problem is when both are set to start automatically on startup of portable apps.
I have been unable to cause the problem with any other method of using the apps.
Is this some timing problem caused by overlapped starting automatically?
It always starts Firefox first, do you think telling it to start Thunderbird first would work, and if so, how do I do that?
So I installed each older version of PortableApps and copied in my current Thunderbird and Firefox. The problem still occurred in versions back into last year, so it is not a PortableApps problem, something changed in some version of either Thunderbird or Firefox (or Windows 10?).
Anyone know which it was, and what the fix is for this?
See here: https://portableapps.com/node/60315
Containing this answer: https://portableapps.com/comment/240208#comment-240208
Please direct any additional questions within.
Sometimes, the impossible can become possible, if you're awesome!
I'm having the same problem. I use this registry file I wrote myself to associate FF portable with URLs and files: https://github.com/XJDHDR/xjdhdr-random-code/blob/master/Registry/Associ...
As you can see, it associates those things with FirefoxPortable.exe (not Firefox.exe). However, I have noticed the issue jim g noted and I traced it to specifically the "Start Automatically" option.
- If FF Portable is not running and I open a link, FF Portable starts with my profile loaded and opens the link in a new tab.
- If FF Portable is running but I opened it by either double-clicking FirefoxPortable.exe or by clicking on it in the PortableApps Launcher, opening a link will open a new tab with that URL.
- If FF Portable is running but it opened because I launched the PortableApps Launcher with the "Start Automatically" option ticked, opening a link pops up the "Another instance of Firefox is already running" error.
The question is: What is the "Start Automatically" option doing differently compared to launching it normally?