Strange errors

[Meyer]

Recently upgraded to 6.3.

for some strange reason when i log in with ubuntu - firefox i get no errors. I can send campaign test emails.

But when i log in from windows pc using firefox or ie I get errors, and when i send a campaign test mail it does not go through but ges stuck in email que? any ideas

[sts]

Do you use the same Firefox version on both computers?
What kind of error messages do you get?