Setting up a backup for a networked drive

I have just installed ATIH 2013 on my new computer. I have successfully backed up the C drive. I am now trying to back up the network drives, which I was successfully able to do on my older computer using ATIH2009. I had to import the settings just to enable me to find the network drives. However, I have now done that, I just wanted to change the shcedule, and when I saved the changes it asked me for a Windows Account and password, which I do not have. What do I do to either acknowledge this or by pass this? I have setup a login user account with password, but this does not seem to work. Any ideas?