User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9b4) Gecko/2008030714 Firefox/3.0b4 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9b4) Gecko/2008030714 Firefox/3.0b4 Firefox 3.0b4 "starts"( Firefoe.exe shows up in task manager), but fails to display anything, when Firefox is started, from Thunderbird 3.0a1pre (2008032402) ie., clicking on a link in an email, Firefox 3 interacts normally with Thunderbird 3 if Firefox is first started manually (ie. dbl click Firefox icon)... then actions started from Thunderbird interact normally with Firefox 3 (ie; clicking on a link in an email) **** Once Thunderbird has tried to open Firefox and failed, a Manual try (dbl click the firefox icon) also will not work,,, To get Firefox to work at this point, "firefox.exe" must be stopped using the Task Manager.. Now Firefox can be started with a dbl click of the firefox icon Reproducible: Always Steps to Reproduce: 1.Make sure "Firefox.exe" is NOT running in task manager 2.Start Thunderbird 3.0a1pre (2008032402) 3.Pick any email with an ad that has a URL link 4. Click on a linked picture 5. Nothing happens and at this point the only way to get Firefox to work is to stop it using Task Manager and then a manual start (dbl click the firefox icon) Actual Results: 1.Firefox is NOT running - verified in Task Manager 2. URL linked ad is clicked 3. "Firefox.exe" starts - verified in Task Manager 4. NO display of Firefox window or anything else related to Firefox 5. NOW manually dbl click the Firefox icon to try to open Firefox 6. NOTHING happens 7. At this point Firefox can't be started by clicking on the firefox icon either 8. Firefox must be closed using task manager and started manually 9. Once Firefox has been started manually, Thunderbird interacts properly. Expected Results: *** Firefox has NOT been executed at this point ****** 1. Start Thunderbird 2. click an ad with a URL in an email 3. Firefox starts 3. be taken to the URL **** AGAIN... Everything works normally IF Firefox is MANUALLY started PRIOR to an action by Thunderbird. It does not matter if Thunderbird is started first as long as Thunderbird does not try to access Firefox before Firefox has been started

4-30-2008 - Found the same problem exist in the latest updated version of Firefox 3 beta 5.

Same problem exists in Firefox 3.0 set up to choose one of many profiles on start. Link clicked from Thunderbird 2.0.0.14. O/S: Windows XP SP3 up to date with patches. When Firefox is already up and running, clicking on the same URL in the email works as intended. The problem happens only when Firefox is not running, and when it happens I find a Firefox.exe Process in the task manager, but no Application.