DreamWeaver is not a web server and so can access files in folders outside the DocumentRoot which is the \xampp\htdocs folder of the Apache server - configuring DreamWeaver is not supported in this forum.
The Apache server can access files and folders in the DocumentRoot only by default...
...but there may be a solution for you in this on topic page of answers
on the Stack Overflow Q&A web site or the DW web site may also have a configuration solution.
Please let us know if you were successful in finding a solution.