Hi Rob,

When you connect your Excel shared drive use the Universal Network Connection(UNC) path vs. the assigned letter.

Please read this Tableau Knowledgebase article.

“Set up the shared network location

Go to the Share files with someone(Link opens in a new window) page on the Microsoft Windows site and follow the procedure under "To share files and folders on a workgroup or a domain." Those steps describe how to use the Windows File Sharing wizard to create a shared folder that is accessible inside your organization using a UNC (universal naming convention). The UNC name consists of a server name followed by a folder name, much like a web address, to access your shared folder. Here's an example, where DATATEAM is the name of the computer and shared is the name of the shared location on that computer:

\DATATEAMshared

The location referred to by shared can actually be many levels deep in the folder hierarchy, even though that's not reflected directly in the UNC name.

When you run the Windows File Sharing wizard, you enter the user account or accounts for people who want to share the content. For this procedure, enter the Run As User account, and then set the Permission Level to Read. This means that any process that runs as the Run As User can read the shared location. In our case, of course, that process is Tableau Server.

The last page of the File Sharing wizard displays the UNC path. Make a note of this path and send it to your users so they know where to connect to the shared Excel files.”

Happy Tableau-ing!