Th following are possible causes for this problem:

1. Does the Client or Project name have a slash ?/? in it?. Slashes are not allowed within file names because the computer OS uses them in determining the file location. Try renaming the Project without a slash and try again.
   
2. Is the location of your Documents folder is NOT on the local computer, ie, it's on a server? If this is the case, you either need to return the Documents folder to be local to the machine, or request that AlterMedia customize your database to accommodate the remote location of this folder.
   
3. Is there an existing file with the same name already open? That would prevent a new one from getting made.
   
4. Of course, if the hard drive is actually full, new files can not be saved. Probably not the cause for you, but gotta ask...