How to change user name in Documentum

Server version is 4.X then

Open DA
Go to user properties and click Rename User link
Write the new name
Select Run Now

If 5.x then:

Open DA
Go to User Management and select Users
Mark the checkbox in the left of the user
From Tools menu select Reassign User

Just put the name of the user you want – Its great!  The user does not actually have to exist. 

Select Run Now

Check report in /System/sysadmin/reports/userrename – that will have the name of the user and you can see if it has worked.