We help IT Professionals succeed at work.

windows activation error

Hiroyuki Tamura
Hiroyuki Tamura used Ask the Experts™
suddenly i get notice say my key is not genuine.
0xc004f005 is the error code.
do you know how to fix it?
it's windows 7 ultimate
Watch Question

Do more with

Expert Office
EXPERT OFFICE® is a registered trademark of EXPERTS EXCHANGE®
Windows 7 will install with a default key (no key required to install Windows), but will ask for a valid key after 30 days.  The error code you're seeing is because you've probably gone past the 30 day grace period.  Check your Windows packaging for the key and enter it when you boot into Windows.  There should be an Activate Now link.
If you have a genuine windows cd, use the key it has or else go to the nearest internet access and opt for a genuine windows license (for u it would be single user license as U are using it on a single computer).

if you are not ready yet you can extend the grace period.
it can be extended from 30 to 120 days LEGALLY.

to extend;
1. open command prompt( type"cmd" in run).
2. Type any of the following commands into the command prompt, and then hit Enter:

sysprep /generalize

slmgr.vbs –rearm

rundll32 slc.dll,SLReArmWindows

slmgr /rearm

this would extend the activation 30 days .


1.U can use this only 3 times that is 30*3 =90days.
therefore u get 30+90=120 days grace period.

2. Use it only after the 30 days period had expired each time.
NikSystems Specialist
Here is the original topic of this info:

Also, if you still don't have the key, you may extend the grace period to 120 days without providing the serial key.
Hiroyuki TamuraField Engineer


it has been activated for two years. and suddenly get deactivated...
does this happen often?
NikSystems Specialist
2 years? Windows has been released on Technet in September 2009.
NikSystems Specialist
Anyway, I know you won't give me points for this post, but I know that upgraded WGA (windows genuine advantage) tool was released with other updates yesterday.
This means your Windows are not genuine. I don't say it is your intention or fault, but there it is. If you have a valid license, you should contact Microsoft support.