If you are installing Windows 7 SP1 or Windows Server 2008 R2 SP1 then you can get error code 0xC000009A and due to this issue you can’t install it successfully. Windows 7 SP1 is the updated version of Windows 7 which has some advanced features such as it include previously released security, performance, constancy updates for Windows 7. IF you install Windows Service Pack 1 (SP1) then it keeps Windows 7 up to date. It adds support for AVX and downloaded with updated. If your system has more than 10 languages installed and you try to install Windows 7 Service pack 1then it stopped with the given error message-
Cause of this error:-
If you are getting error code 0xC000009A when you try to install Windows 7 SP1 in your system then it means that you have more languages installed and each language pack increase many open registry key handles but the number of registry key which is handled for subkeys are limited to 65,535 so if it increase then it stopped the installation. As we know that when we install any software or application then its detailed stored in registry file which act as a database file of the system so if it cross its limitation then it can’t perform any activities. If system is not updated, not well configured, malicious programs injected then it may be the issue of error code 0xC000009A when you try to install Windows 7 SP1 or Windows Server 2008 R2 SP1.
How to fix this problem:-
If you want to fix error error code 0xC000009A when you try to install Windows 7 SP1 or Windows Server 2008 R2 SP1 then first you have to restore the system then update it because if any setting or file of the system is missing then it can be solved with system restore and after update system files also updated so installation will be supported or helps to install Windows 7 Service Pack1 successfully. Update all supported x86, x64 version of Windows 7 and x64 version of Windows Server 2008 R2 package then try to install it. You must also do a very common and useful process called system scan because it is compulsory to be sure that the system is protected and there are no issues. You can also use windows repair tool to repair windows files if they are missing because sometime system files gets corrupt or damage so unable to support to the system to run successful and install softwares.