Program installation

Have had difficulty installing Sony Ericson software onto my PC. They have
been no help so thought id post here and see if anyone had a similar prob
witha different program.
Install seems to go fine. Progress bar reaches 100 % but then reverses back
down to zero. Have uninstalled the program. Deleted it and cleaned the
registry with Regvac. Not all the Sony keys can be removed. Are there some as
standard within the registry. Is this the problem? Any suggestions?

My system is fully updated with windows update

Any suggestions?

Thanks