"Common" Folder keeps popping up

First off, I would suggest that you not allow all users to have Admin. privileges.

Next:
Run this: Disable/Remove Windows Messenger to remove Windows Messenger. Do not confuse Windows Messenger with MSN Messenger because they are not the same. Windows Messenger is a frequent cause of popups.

Can you not delete the c:\program files\Common folder? If not:

download The Avenger by Swandog469, and save it to your Desktop.

* Extract avenger.exe from the Zip file and save it to your desktop
* Run avenger.exe by double-clicking on it.
* Do not change any check box options!!
* Copy everything in the Quote box below, and paste it into the Input script here: part of the window:

* Now click the Execute button.
* Click Yes to the prompt to confirm you want to execute.
* Click Yes to the Reboot now? question that will appear when Avenger finishes running.
* Your PC should reboot, if not, reboot it yourself.
* A log file from Avenger will be produced at C:\avenger.txt and it will popup for you to view when you login after reboot.

Now run CCleaner.

If you still have issues, run the C:\MGtools\GetLogs.bat file by double clicking on it. Then attach the new C:\MGlogs.zip file.

 

Your logs are clean.........If you are not having any other malware problems, it is time to do our final steps:

1. We recommed you keep SUPERAntiSpyware and Malwarebytes Anti-Malware for scanning/removal of malware. Unless you purchase them, they provide no real time protection. They are useful as backup scanners. They do not use any significant amount of resources ( except a little disk space ) until you run a scan.
2. If we had you use ComboFix, uninstall ComboFix (This uninstall will only work as written if you installed ComboFix on your Desktop like we requested.)
   
   • Click START then RUN and enter the below into the run box and then click OK. Note the quotes are required
   • "%userprofile%\Desktop\combofix" /u
     
     • Notes: The space between the combofix" and the /u, it must be there.
     • This will uninstall ComboFix and also reset hidden files and folders settings back to Windows defaults.
     
     
   • Delete the C:\combofix folder from combofix (if it exists)
   
   
3. Any other miscellaneous tools we may have had you install or download can be uninstalled and deleted.
4. If running Vista, it is time to make sure you have reenabled UAC by double clicking on the C:\MGtools\enableUAC.reg file and allowing it to be added to the registry.
5. Go to add/remove programs and uninstall HijackThis.
6. You can delete the C:\MGtools folder and the C:\MGtools.exe file. You can also delete the C:\MGlogs.zip
7. If you are running Vista, Windows XP or Windows ME, do the below:
   
   • Refer to the cleaning steps in the READ ME for your Window version and see the steps to Disable System Restore which will flush your Restore Points.
   • Then reboot and Enable System Restore to create a new clean Restore Point.
   
   
8. After doing the above, you should work thru the below link:
   
   • How to Protect yourself from malware!