Get the mapped file path

I would like to know what is UNC path for my mapped drive

For instance if the user browse on the html input file and selects some mdb on "J " drive and if I pass this path to  open Access Database I get error

"is not a valid path.  Make sure that the path name is spelled correctly and that you are connected to the server on which the file resides. "

Now instead of selecting J drive if  I select this file from MY Metwrok places and then browse the appropriate folders so that I have the correct path I can open my Access database

I tried using Registry keys to get Mapped path details it works when I run from Local Machine but on server it gives me error

Also  is there a way I can open files on Clients /Users C drive

Thanks in Advance

 

 
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