Removable disk drives inaccessible

Well, in short, I can only access my removable disk drives (two: a CD-RW and
DVD-RW drive) on a single user. I start up and login, and everything seems to
be in order. However, when someone else uses the computer and "fast user
switches" to their account, every time they try to access a drive, it gives
an "Access denied" error.
What account it works on is variable, per my observation the first user to
logon. I have been using this computer for quite some time without this
trouble, and this started happening shortly after I installed my new DVD
burner. I am also having other troubles with the drives, but most of them are
the subjects of different postings.

Any help would be greatly appreciated.