Fiddler 2 - Can't open/load it

Question

I can't open fiddler after installed.

I tried Start/All Programs/Fiddler2 and C:\Program Files\Fiddler2\Fiddler.exe; no success.

There was a loading icon on my cursor, but fiddler did not load.

I checked my task manager, and I sometimes saw fiddler.exe under processes tab, but it quickly disappeared. There is no error message.

I uninstalled Fiddler2, reinstaled and still same problem.

Uninstalled .Net Framewrok 2 and installed .Net Framework 3. Uninstalled Fiddler2 and installed again. Nothing happens, still same problem.

I have been using Fiddler 2 for a while in this machine, with great success, but after formatting my pc and set up all again, i started getting this problem.

Also, I tried install/uninstall/run Fiddler in Safe Mode (you know, the safe mode you get while pressing F8)

Can anyone please help me out, please?

Thank you in advance!

P.S.: My PC is running Windows XP SP2