If server 2008/2012 the user name will likely be user@domain. Check the formatting server side by right-clicking the folder and going to Sharing > Advanced Sharing > Permissions, the copier user name must be formatted as seen in brackets at the server, it does not matter how it works from a PC or another printer, in this case this is the only acceptable user name format.
Next on the list is to make sure this highlighted entry is not checked in CWIS > Properties > Connectivity > Protocols > IP > DNS
Also, check that the time is not off by more than 3 minutes if Server 2012 CWIS > Properties > General Setup > Date and Time
And lastly, when you create a repository or template, if the port lists 139, it is likely an old firmware that will need to be updated, so if all the above fails, upgrade to the latest firmware and try the scan immediately after.