My bad
"You could use the following command utility called junction from Mark Russinovich Sysinternals - www.sysinternals.com

junction c:\my_symlink "U:\networkpath\dir"

you could now set your DocumentRoot directive in as C:\my_symlink

restart Apache and that should work.

This however requires that you set have mapped the network drive correctly using net use command (perhaps with the peristence option)"

"i have found a solution, if i run apache from command line, it worked. but not from service."