To change and disable the execute bit of WgaLogon.dll:

First of it only works with NTSF, not with FAT32

Turn off Simple File Sharing in Tools -> Folder Options -> View tab. ( in windows explorer/ tools/folder options/ view)

Right click WgaLogon.dll in Windows Explorer and open the Security Tab.

Click Advanced button.

Uncheck the Inherit box at the bottom.

Click the Copy button.

Click OK.

Go through each listed user/group and remove the “Read & Execute” permission for WgaLogon.dll, leaving the “Read” permission as-is.

Click OK to apply the permission changes.

Close the file properties dialog.

Restart the computer.

Turn “Use simple file sharing” on (optional).

Optionally, steps suggested by PSNet which has the same effect - disabling WgaLogon.dll.