One thing to check, in system preferences>sharing make sure that file sharing is checked and when you highlight file sharing click on the options button and there make sure you have “Share files and folders using SMB” checked and below that it will list have the user listed and checked to enable windows file sharing.
UPDATE: Wiped my internal HDD and freshly installed Sierra OS using a new user and password. Reset the ATV to factory defaults (with latest OS) and reinstalled Infuse. Created a new share and I still cannot connect.
I’ve got the same issue. I purchased Infuse Pro 4 back in August and have only used it a few times. Trying to use it over the the holidays and I’m getting the same error about my username and PW not being correct. I went and verified by doing a file share between my rMBP and my wife’s MBA and had no issues connecting with the credentials. However, I cannot get Infuse Pro 4 or the free v5 version to connect via SMB.
I have confirmed that I have file sharing enabled, added the proper folders/drives as well. Verified SMB folder sharing was enabled as well, and as mentioned above, verified I can remotely connect with the user creds. Also note my wife’s MBA is still running Yosemite (while I have the latest version of Sierra).