Hey, thanks for the replay.
i will give another update, the 404 error was occurred because a bad configuration of the "auth" rule on my TMG, i fixed it and now it works fine for both Chrome and Firefox.
It happens both internal and external, claim based worked fine, all the URLs are working fine.
it happens only with Explorer, i tried to add the "STS" URL to the trusted sites also didn't work .
appreciate your help.
