When creating custom templates using ArcGIS Pro, there is something you should know that happens if your template references data or folders that are located on mapped drives. A mapped drive is one that is referred to by a drive letter, such as the C: drive, which is normally the local drive on your computer, or the M: drive, which is located on a network file server.
While using ArcGIS Pro, it is preferred that you don't use mapped drives, especially when creating templates. It's preferred that you use a Universal Naming Convention (UNC) path. So, what is a UNC path? This is what IT people use to connect mapped drive letters to a folder on their server. A UNC path looks something like \\GIS_Server\GIS_Data_folder. GIS_Server is the name or IP address for the server on your network. GIS_Data_Folder is a share created by the server administrator on that server to allow others on the network to access the files contained within it.
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