Depends how do you know you have it was it detected (by what) and what is the detection name?
Follow the programs mentioned here in order usually stopping at before hijack this suggestion
Firstly scan in virusscan updated and scan in safe mode.
Then run Getsusp add your email to the preferences so Mcafee can update you to what it finds and what is has done. This allows it to create new dat detection files for issues it is not aware of Getsusp.this program is detection only and will uplaod to mcafee any unknown and suspicious files.
Then follow by stinger fake alert.
If no good scan with Malwarebytes and superantispyware
upd32.exe is a critical system problem that is commonly caused by an unstable system registry or corrupt system files that are required to run Windows smoothly.