Windows 7: DVD's

I am having problems with my DVD's Registering can anyone help me it work initially now all of the sudden it doesn't work.

I'm not sure what you mean but I found this to be a common DVD problem in Windows 7:

Have you tried opening the registy key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E965-E325-11CE-BFC1-08002BE10318}

and deleting "Upperfilters" and "Lowerfilters" values?

that worked thank you very much