A deleted copy of this <File> file already exists in this project.

This warning has the following cause and solution:

• When a file is deleted in a project, it is no longer displayed but it still exists.  So when you attempt to add a file of the same name, Dynamsoft SourceAnywhere for VSS prompts you to decide if you want to recover the deleted file or add the one you indicated.
  
  Choose Recover this file if you want to recover the deleted file in the project, and not add the new file.
  Choose Purge this file and add a new file if you want to add a new file.
  Check Apply to all items to have your choices in this dialog box apply to all other files you want to add.