suddenly unable to add port forward for a static LAN IP
I've been a Comcast Business Class customer for over 3 years using the same device a Cisco DPC3941B
DOCSIS Software Version: 184.108.40.206_220.127.116.11
Software Image Name: DPC3941B_3.9p17s1_PROD_sey
Advanced Services: DPC3941B
My DHCP scope is setup to start at 10.1.10.100 therefore .1 thru .99 are reserved as static addresses on my LAN for devices. These devices have (again for YEARS) been setup with port forwards under the Advanced - Add Service section of the DPC3941B.
As of two weeks ago I am no longer able to add new port forward rules for ANY IP outside of the DHCP scope. I am also unable to edit existing rules for IPs which are static / not in the DHCP scope.
When I attempt to add a new rule I'm simply prompted with this very basic error window "Failure Please check your inputs!" It does not matter if I manually enter the IP or select the device from the CONNECTED DEVICE button / list the result is the same.
If I attempt to edit an existing rule for a device within my static range I get a similar window that reads "Unable to edit rule".
I restarted the modem numerous times that did not resolve the issue.
I've attempted to change the DHCP scope (to default) save - reboot - update it with what I require - save - reboot again. This does not resolve the issue.
Beyond my better judgement I finally performed a factory reset on the device and now all my rules are gone and the problem persists!!!!
If I instead try to add the rules under Advanced > True Static IP Port Management it just tells me the IP I'm inputting isn't a static address.
Upon further troubleshooting I have learned the device will ONLY accept a port forward rule for an IP within the DHCP scope. YES the option is UNCHECKED under GATEWAY > FIREWALL >IPV4 relating to disabling firewall for true static IP subnet only. I've tried checking it save - reboot - try again - uncheck - save - reboot it doesn't matter I can no longer add static IPs as an input to the Port Forwarding section - where I WAS able to do this up until 2 weeks ago.
My original ticket for this issue was put in Saturday the 19th without resolution!!! I've since called Comcast Support a minimum of 7 times. I finally demanded the modem be replaced since I'm unable to get any type of competent support. This of course did not resolve the problem.
I am confident the issue must reside in something changing in the software / firmware pushed to the modem.
Upon searching older threads here I found numerous people with similar issues and every single time someone from Comcast tells them to take it to PMs. I WANT A PUBLIC RESOLUTION!
I am frustrated out of my mind as its been over a week now without resolution!!! As I write this I am yet again left waiting for someone to call me back (from my 8th call yesterday) to tech support.