The system cannot find the path specified.
This simply means that the path is incorrect that you are using to refer the path.
Either, use a absolute path directly OR use a correct relative path. You would need to make sure that the path is correct such that file is found and used.
For relative path, you can try this Tip and resolve the path correctly before setting the source of the file:
Resolving Paths in a Multi-Folder WebSite[
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