CD-R

I am having many problems suddenly with my CD Rom /
rewriter. Various errors occuring including:
When trying to write to a CD-R - error message C00D11BF
(Cannot copy files to recordable disk);
When inserting a CD to play music - C00D11C0 (Cannot play
the file);
C00D11C4 (Cannot find the proxy server);

All of these have just suddenly occurred today, whilst
earlier I was successfully carrying out actions. I have
checked Microsoft Update, but there are no updates.

Any suggestions?

Drew