Serial number already in use Generals and Generals Zero Hour FIX Easy  Solution .
 Serial key already use
Just follow these steps.

Open Start menu.
Type "Regedit" in search box.
Open Regedit
A new windows will appear.
There choose
HKEY_LOCAL_MACHINE
Then Choose Softwares.
Then Electronic Arts
Then EA Games
Choose Generals
Choose ergc
In ERGC open "Defult" file
In Value Data
Just change any digits . Type any number.
Press "OK"
All Done

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