In your xampppath\apache\conf\extra open file httpd-xampp.conf and find the below tag:
# Close XAMPP sites here
<LocationMatch "^/(?i:(?:xampp|licenses|phpmyadmin|webalizer|server-status|server-info))">
Order deny,allow
Deny from all
Allow from ::1 127.0.0.0/8
ErrorDocument 403 /error/HTTP_XAMPP_FORBIDDEN.html.var
</LocationMatch>
and add
"Allow from all"
after Allow from ::1 127.0.0.0/8 {line}
Restart xampp, and you are done.
In later versions of Xampp
...you can simply remove this part
#
# New XAMPP security concept
#
<LocationMatch "^/(?i:(?:xampp|security|licenses|phpmyadmin|webalizer|server-status|server-info))">
Require local
ErrorDocument 403 /error/XAMPP_FORBIDDEN.html.var
</LocationMatch>
from the same file and it should work over the local network.