firefox portable linking problem or doesn't use right settings!?

as firefox portable starts by using the desktop shortcut but gives only error window by trying to start a link from an app...
i think firefox maybe sets some setings in system which it doesn't find anymore or...
or he don't find the right firefox as i found at least 3 of them, with separate directories.
i deleted one, situation unchanged.
maybe that's the problem or both, including a drive problem.
i hope i can first check this, as don't get as quick to check the drive. too much at moment.
many thanx!
EDIT
how to check if firefox portable settings are right?
i supose there is a problem somewhere in the setting or function linking in firefox portable or maybe windows.
don't know what's the dumb problem on, but firefox portable is known for such things.