Open the registry editor. Start-> Run-> type “Regedit” without quotes.
When you select “Registration”, at the right hand side, you would see “PIDKEY” that has 25 alphanumeric characters. That is the product key.
If you do not find it under registration, expand “Registration” and select the next key under that . Ex: 1000.0.0000 and there we should be able to see the PIDKEY.
If we want to check for Visual studio 2005 look for : HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Visual studio\8.0\Registration
Content by : Parameswary Annamalai
Reviewed by : Soumitra Mondal