hallo, hilft das hier weiter?!: www.camp-firefox.de/forum/viewtopic.php?t=97969

Check the target field in the Firefox desktop shortcut and make sure that you do not start Firefox with the -no-remote switch or have set the environment variable MOZ_NO_REMOTE=1 (Control Panel > System > Advanced > Environment variables).

• http://kb.mozillazine.org/Opening_a_new_instance_of_Firefox_with_another_profile

The variable MOZ_NO_REMOTE is not set. I use only the default profile. I have had multiple in the past, but after reinstalling FF, only one. But I have multiple Thunderbird profiles ... is there may be a depdendcy ?

Did you also check the Firefox desktop shortcut(s) and maybe the properties of the Firefox.exe program in the Firefox program folder?

do you happen to use sandboxie (or for that matter any other security software that might interfere)? http://www.sandboxie.com/phpbb/viewtopic.php?t=13330

I use Only Norton Internet security. dissabeling changes nothing

when you initially open firefox by pressing the windows-key+R & opening firefox.exe, does the problem occur too when you open external links subsequently?

Yes ! open firefox by pressing the windows-key+R & opening firefox.exe then open Thunderbird for examaple ... same Problem

& can you replicate this behaviour when you launch firefox in safe mode once too?

Beheben von häufigen Firefox-Problemen mit Erweiterungen, Themes oder Hardwarebeschleunigung

Ok I will do. Back soon ..

isnt it strange, that it works from 1 external applikation if I klick a link. any other app with links came up with the same error as wehn I start FF directly. Something locket the execution either for FF start only or 1 App+FF if it is invoked from there

it sounds a bit like some sort of firewall is controlling/limiting the access to the browser but i'm not sure if norton has such capabilites since i don't use it myself...

ok ... I come closer ...

I figured out, that the problem depends on Thunderbird !! Indipendend if I start in save mode or not I can use external links from other diffrent Apps, as long I dont use a thunderbird link !

In thunderbird I use different profiles .. and some add ons ... we should have a closer look threre

save mode thunderbird ... same prob.

can you look if the thunderbird shortcut contains the -no-remote switch (that has been a solution to the same issue here) or also reset firefox as default browser...

I use: "C:\Program Files (x86)\Mozilla Thunderbird\thunderbird.exe" -no-remote -p xxxx-profile

I thougt the problem is happen, if I use that switch opening FF not TB ! Ok ... how could I use profiles without that switch ?

yes, this is really strange & it looks like firefox is somehow inheriting the -no-remote parameter from the thunderbrid instance. this is bug #382477, which hasn't been addressed for a long time...

bad news ... and it looks that nobody works on it ! any Idea for a work around ?

I find a workaround you can use the profile switcher Add-on

Anyway I hope it will be fixed !

Thx for your help