NSF database cannot be opened

I have a Java application which is enumerating emails from a NSF. The NSF is placed in a CIFS share. I open the database (NSF) from a machine A. It is successful.

I close the database on machine A

I then open the database from another machine B. It is also successful.

I close the database on machine B

However after sometime, I cannot access the NSF from one of the machines.

The session.getDatabase() (Java) does not open the database.

After session.getDatabase() if I call db.isOpen() it returns false.

Can anyone let me know if there is any issues in accessing the same NSF from multiple locations ? Is there some state/cache written to the NSF when calling getDatabase() or other such Java APIs ?