Can't add user to a collection

I’m using the latest Recast RCT free tools.
I can’t add a user to a user collection.
Using the “Add Users to Collection(s)”
I’ve tried every variation on user name but nothing works.
Message
Error: Not found for user name
Error: Generic failure for domain\user (Last, First)
Error: Not found for mail address
Error: Not found for resource id

The tool searches for the SMS_R_User.UniqueUserName field, which is of the form domain\user. Since ‘’ is a special character in WQL, it needs to be escaped in order to be a valid query. Try using the form domain\user instead.

I’ll try to add a message to the tool in the next version that describes the expected input.

I’m using the form: domain\user
Central_Office\doitdb1
Parolenet\WhiteA
They get a generic error.
Are there some kind of additional escape characters that must be included?
Like Central[_]Office[]doitdb1 which doesn’t work.

It looks like the forum escaped my text. I meant to say try the form domain\\user instead:

Adding the second \ works very well, thank you.
domain\user

I see where the software took out the second \ domain\\user