How can i change my XP theme?

I cant change it because when i right click then go to properties, the themes tab is blocked. How can i change my XP theme?
Your hard drive is probably dirty so try running check disk first then try again to change theme.How can i change my XP theme?
If this is a work computer then your company possibly has blocked via Group Policies. Certainly I don't know how your company is set up but speaking for my company we block desktop backgrounds via Group Policies. Ask your IT person (if this is a work computer) to see if they have blocked this on your computer.



If however this is a home computer then it could very well be that you are infected with malware.