You may receive this message when you attempt to open an MYOB company file. While it's unlikely there are actually 10 company files open in your MYOB program folder, this message indicates there are 10 lock files in the folder where your MYOB company file resides, and only 10 lock files can be created in one folder.
MYOB accoutning programs track users ID's as users enter and exit the program in a file named lockxxxx.flk. One lock file is created in the folder where a company file is located when the first user opens a company file; this one file tracks all the users of the company file. The lock file is deleted when the last user exits the company file, but if a company file is closed incorrectly, the lock file may not be deleted.
You may wish to have your system administrator perform this task since he or she is familiar with the configuration of your network and may be better prepared to respond to this situation.
The 10 lock files must be deleted manually.
You should then be able to open the company file.