Error "Can't import: not a directory" when attemping import task

While running the import task to upload content from a directory, the following error may be observed in the nexus.log:

2020-09-15 12:54:35,994-0400 ERROR [quartz-7-thread-16] *SYSTEM com.sonatype.nexus.exportimport.internal.importtask.RepositoryImportSource - Can't import C:\Users\test: not a directory

This error will occur if the directory being imported is located on the client machine and not local to the Nexus Repository server. The import task running on the Nexus Repository server needs access to the files being imported. The path specified for import needs to resolve to a valid location on the server.