Your local working copies should be stored on a local drive on your own computer. Storing your working copy on a network will cause serious performance problems and is not permitted (the project will be read-only).
To use Subversion (SVN) with your Help+Manual projects you need to perform three steps.
1.Use the SVN management tools to create a repository database for your project on the server. If you are a single author working on your own you can use Tortoise to create a local file-based repository (see further below).
2.Load a copy of your project into the SVN repository. This is the master copy of your project that all your subsequent work will be synchronized with.
3.Each user who will work on the project then needs to make a linked local copy of the master copy from the SVN repository. This is the copy that each author will work on. This local copy must really be local, stored on a local drive on your own computer. Do NOT try to store it in a network drive – it must be local.
NEVER EVER store your working copy on a "managed" drive like DropBox, OneDrive or iCloud Drive!