Yes you have a gosth in your pc,but i think i can help you since i have the same problem from time to time....You can try this:
1.Uninstall the p2p apps totaly as you normaly wood do it...Check if its really remove all the files frome the location you installed it on,then open your registry editor and you find it under windows system 32...Now check this two location: HKEY_CURRENT_USER_SOFTWARE and HKEY_LOCAL_MACHINE_SOFTWARE,now look if you find enny registry key left from the p2p apps...If you do delete it for good! Now go to
CCleaner - Home and download the latest ccleaner and install it and run the registry cleaner,then fix all the problem it finds...So restart your pc ,and try now to install the new version you wanna use and it should fix the returning of the old software problem....I hope this can help you,as it helpt me with the same **** problem!