How to change name of .ost / folder in outlook 2013

[Doubts]

I just created a new mail account name@domain.com.

In the past, the folder/ost would be named name@domain.com.

Now, for some stupid reason, the name of the folder/ost is "D".

This is not only annoying but looks silly.

How can I change it back to name@domain.com?

Thanks

PS: Does imap & smtp have DIFFERENT ost naming schemes?

 

[Doubts]

I just created the same account via POP instead of IMAP, and now the folder/ost is named after the email address.

So, am I to assume that when you create an IMAP connection via outlook, you get some whack OST name scheme?

Can anyone break this down for me?