1. Moodle/PHP/MySQL/Apache installed on windows machine?
2. Windows machine set up as a web server on the LAN?
3. Fixed IP or DHCP? Needs to have a static address.
3. Client machine - in this case a Linux box - cannot display images correctly in its browser and the page loses its formatting, layout and styles?
When this happened to me I had to change the network settings on the moodle-host machine. I changed a netmask of 255.255.255.0 to 255.255.254.0 It turned out we had 2 subnets - ask your sysadmin how many subnets you have.
I'm guessing you need to go into the network settings in Windows control panel and fiddle around looking for SUBNET MASK. As I said before, I know very little about Windows settings, I like Linux and Macs
LS (Writing from a Windows Desktop