I keep on getting this error:

Error Type:
Microsoft JET Database Engine (0x80040E09)
Cannot update. Database or object is read-only.
/WROX_ASP/chap15_DL/AddUser.asp, line 13

My database is not read-only. I have checked out most of the IIS settings, everything seems to be configured properly.

I think I had the same problem in Windows XP. Try opening Windows Explorer find the database file (classified.mdb or whatever) righthand click on the file and select properties. At the bottom righthand corner you may see a security notice 'This file came from another computer and might be blocked to protect this computer' Just click on the Unblock button.