Can't scan to samba network folder with MFP 4101fdw !?

[cruiserandmax]

I just bought an HP MFP 4101fdw to replace a M227fdw and I cannot figure out how to setup the new 4101fdw to scan to a SMB network folder on my network that the M227fdw scanned to without issue...

On the M227fdw I was able to specify the samba netowrk folder to scan to entirely via the LCD touchscreen panel on the printer. The netork folder is //happymachine/scan and is accessible to anyone on the network without a login (no credentials needed).

On the new 4101fdw the "Scan -> Scan To -> Network Folder"  option on the LCD panel tells me to conifgure the network scan folder via printer embedded web server or software installed on a PC. I used the EWS and selected Scan -> Scan To Network Folder -> Quick Sets, and tried to add one. For the netork path I put  //happymachine/scan (same as was used on the old printer) and then it makes me choose either of these options:

- Use credentials of the user currently signed in

- Always use the following credentials

I tried "Use credentials of the user currently signed in", and also "Always use the following credentials" (including the login/password for a user that exists on the linux host).

In both cases the entry shows up as an option on the printer's LCD panel interface when selecting 'scan to netowrk folder'  but when I hit scan it says Connecting... and then reports Unable to connect to the network. Check the network, and then try again.

The printer is connected via ethernet. I can print to it from a Windows machine on the netowrk, and that same windows machine can browse to/read/write to the samba share  //happymachine/scan

I am totally stumped at this point. Any help would be greatly appreciated.