why can't i check for update?

hello everyone!
i'm using pd9 and my os version is 10.9.1
when i want to check for update i find that the button was gray!!!
what should i do?

 

Hi tony190,

- Please uninstall Parallels Desktop as suggested at http://kb.parallels.com/116992

- Download Parallels Desktop 9 for Mac from http://www.parallels.com/directdownload/pd9 which is the latest build and install it.

- Your Virtual Machine will remain the same even if Parallels Desktop is uninstalled and reinstalled.

Thanks,
Abdul