How to find out which user is locking a table ?

When you want to make a changes or post something and the following messeage come out:

"table is Locked by another user"

This means that another user is also modifying data in the same table. Navision has locked the table for the user to modify so that no other users can modify the same data at the same time. Any other user who want to modify the same data must wait until the user who locked the table to finish his/her changes first. Once the user has finish modifying the data, Navision will release the table lock for other users to use.

Navision allow you to check which user is locking other users.
1) Go to File-->Database-->Information.
2) Select the Sessions tab.
3) Drill down to the current sessions.
4) Check on the Blocking user id column to find out who is locking other people.