i have a backtrack 5 64-bit KDE installation in a VM. ive got a meterpreter shell on a windows xp sp3 VM. The meterpreter shell doesn't have admin rights. I tried several thinks to get these rights:

getsystem: outcome: priv_elevate_getsystem operation failed access is denied
incognito: i cant get the tokens because im not system
migrate: when i try to migrate to a system process i get a acces denied error
all the modules in the post/windows/escalate folder. The either say they cant find a vulnerability or they say that they cant be excecuted on a sp3 machine

i have looked at every link on 5 pages of google results, non of them giving a sollution.
the wiki only says how to install CUDA when i click on privilige escalation

does anyone know what to do? i cant think of any options any more now. thx in advance!