Looks like only your first screenshot uploaded but I'm willing to bet you need to follow the instructions in the article below, on your Tableau Server machine.
It should be noted that the .tms files already exist with Tableau Server installs so there is no need to create one as the article states. Making adjustments to the ones present should be enough for most situations.
Also, the "version=" needs to match the current Server version -- this is a bit unfortunate for those of us with customized .tms files and in my opinion should be an optional value with a default of the current Server version if not present.
I'm having quite a bit of issues getting the mapping to work. Some of the links inside of the article you posted aren't working and all i really want to do is create a cache of the default map in Tableau from OpenStreetMaps. I'm not able to locate the already existing .tms files Toby is talking about either.
I was able to use one WMS i found online, which worked on tableau desktop, but once I uploaded it to the server, I received an error stating that it could no longer connect to the WMS.
Is there any way to create a cache for the default tableau mapping without creating a TMS or getting the WMS servers to work? Once again, the original map DOES load on the server, but wont load when I download the view as a PDF or show up in e-mails.