I installed an application (WonderWare Intouch) which asked me to provide a login account for its services.
I gave it my login but it said 'Account already in use' and asked for another account to be entered. I entered a random account name (acc1) and password and the install was happy and proceeded on.
At the next stage of the install there was a problem and i had to cancel. I resolved the problem and re-ran the install. The second time around it again asked for a login account so i re-entered the account i had used on the previous install (acc1) but i received the response 'Account already in use' so I then had to create yet another account login (acc2).
The install completed and the app is running fine but when I went to Admin>Users I could find neither 'acc1' or 'acc2'. I was intending to have a tidy up and get rid of 'acc1' but where is it?. It was obviously created during the first install and did/does exist because the second install detected it!!