warning -- I am using this firmware on an ASUS RT66u router -- I know this is a linksys forum, but I am posting here since the contact us info on the advanced tomato site suggested this forum. I think this is a firmware related issue not related to hardware. The problem I am having is that I wish to use my Windows Server for DHCP and disable the DHCP server in on the router. When I do this, randomly none of the clients utilizing wireless are able to obtain an IP. Wired clients on my network work perfectly fine. Details -- I have a flat IP network, no other subnets / vlans. The only routing in place is the RT66U for internet access (obviously the default gateway in my network). Only 1 wireless network setup (mirrored for 2.4 / 5.0 frequency ). Single internet connection (no dual wan). No USB or any other devices plugged into the router. No VPN, QOS, SMB, or NFS. Running Firmware version: 1.28.0000 MIPSR2-3.5-140 K26AC USB AIO-64K downloaded from advancedtomato com downloads Checked MD5 Hash to ensure no corruption on the download. The existing setup has worked perfectly with the original firmware on the router. Wireless and wired devices got DHCP from my windows server. As soon as i put the Advanced Tomato firmware on my router I started having issues (yes I turned off the DHCP on the router). The reason I say I am randomly having issues is that because it will work for a little while, then it just stops. Nothing I do will resolve the problem (reboots, etc). Then after a day or two it will work for a little while (without any intervention) and then stop working. When I setup the router to provide DHCP server, it works flawlessly (of course disabling the DHCP service on the windows server). Troubleshooting I have done. #1 Reboot all equipment (including windows server and network switch) #2 reflash router utilizing all the steps to clear NVRam and resetting back to factory defaults as described in the install guide. #3 Triple checked that DHCP was unchecked in the router config #4 Put in a spare TP link wireless router (Factory) to make sure DHCP from the windows server worked (It did) #5 Wireshark captures on the Windows Server show that its getting a discovery request, sending an offer but that is it.I am not seeing a request back from the client. I am assuming something in the router is blocking that. my question is does anyone have any idea what could be causing this issue and has anyone successfully running DHCP from another server ?