I've just purchased a Sansdisk 1G U3 drive and have installed portable Firefox on it. When I use the launcher to start Firefox on my laptop it works like a charm. Ditto for trying to launch other programs like Skpe and OpenOffice. When I tried to use it on my work computer, every program launches except portable Firefox. I get the above error message. I tried reinstalling Firefox. Same error message occurs.
First off, are you using the latest Firefox for U3 from PortableApps.com (version 1.5.0.70)? Second, what is generating that error. Is it a Windows error message? A U3 error message?
If you're on the most recent version and it's a U3 message, most likely your work antivirus is silently preventing it from running. There have been a few false positives lately with some of the major antivirus vendors.
Side note: Moved to the U3 forum. Firefox for U3 and Firefox Portable are two different applications.
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