Hi gencinas,
Thank you for using the forum.
I would suggest looking at the following as a potential solution for your issue.
Solutions for : SMB Workflow Scanning Fails With "Login Failure, Check User Name and/or Setups" Message
http://www.support.xerox.com/support/WC780X/support/en_US.html?objGUID=16764
If that doesn't help then you may consider contacting the support center Fast Track to the Expert