Community Forum

Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

Regular Visitor

Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

Brand new Comcast subscriber, up for about 2 weeks now.

 

I'm trying to setup port forwarding on the XB3 and I'm seeing some really unusual behavior:

  1. I successfully created 2 (of 7 or so that I need) Port Forwarding rules about a week into the service and just before Thanksgiving I noticed both rules were gone.

  2. When attempting to create new Port Forwarding rules, recreating the 2 rules that went missing plus new rules, I consistently receive the error message below after clicking save.  There is no on-screen visual feedback indicating that I've failed to provide some information or that the information provided in field X was invalid  (So to be clear, there was no no red text under any fields or explanation about what it didn't like or what I failed to enter)  Error message: 
    • Title: Alert
      Body: Failure!  Please check your inputs.

 

The process I'm following is as follows:

  • Login as the admin
  • I'm going to Advanced > Port Forwarding
  • Port Forwarding was already Enabled when I created the rules
  • I'm clicking the +Add Service button to create the Port Forwarding rule
  • I wait for the page to fully load before attempting to enter in any information (seems to be populating the connected devices selection window which takes a while)
  • On the port forwarding screen:
    • Common Service is always defaulted to Other and I'm leaving it that way.
    • I'm manually entering in a Service Name consisting of only letters
      • No numbers
      • No special characters including spaces, dashes/hyphens etc.
    • When it comes to the Server IP Address field, I've tried two methods to populate it:
      1. I'm manually typing in the Server IP Address which I've confirmed is the correct IP
        • I verified this two ways: (1) from the device it self and (2) under Gateway > Connected Devices / Connected Devices > Devices in the XB3
      2. Clicked the Connected Device button, selecting the radio button for the host (device) in question and clicking Add which populates the IP field automagically.
      3. I enter the port I need opened under start port
      4. I enter the same port opened under end port
        • After all, I only need a specific port opened, no sense if opening a range
        • Also, I tried leaving the End Port field empty, but it doesn't like that, spitting out "This is a required field." in bright red under the field.
      5. I click the Save button 

Consider this section Step 6 continuing from above.

What really gets me going is that seemingly without any apparent cause, I get two different experiences:

 

Result 1: "Successful" Save

  1. If it lets me save the rule, I'm taken back to the Port Forwarding screen and I see it there.  Good.
  2. If I do either of the following, the rule is suddenly missing:
    1. navigate to another screen
    2. [attempt to] create a new rule

Result 2: Failure! Please check your inputs.

  1. I attempt to create a new rule and fails with: Failure! Please check your inputs.
  2. Nothing I try seems to fix that problem.
  3. I cancel the existing rule, try again but get the same error, or Result 1 above.

 

From what I can tell, its not unique to the host/device I'm creating rules for.  What I mean by that is I can recreate the problem even if I'm creating rules for other hosts/devices be it the same ports or different ones.  And just like above, its hit or miss: It either "saves" and then disappears, or I can't save it at all.

 

Before I go deeper down the rabbit hole (e.g.: factory resetting) looking for advice on what I should try next.

 

If you've read this far, here's some additional potentially useful/helpful information:

  • Model: XB3 DPC3939
  • Stock SW Ver.: dpc3939-P20-18-v303r204113-131030aCMCST - zero customizations made to it prior to the creation of the rules (not like there's that much to configure anyway...)
  • Modem has been power cycled (rebooted) at least once.
  • Port Forwarding problems described above occurs no matter host/device: PS4, Windows, Linux/Unix, NAS Device, Android devices and so on.
  • Attempted to create the rules on 3 different computers using two different browsers.
  • None of the documentation here contains anything of substance [relating to Port Forwarding].
  • This post states that Parental Controls must be enabled, and the devices must be added in order for this to function.
    1. Where is this documented?
    2. What is the technical reasoning for this behavior?
    3. I enabled Parental Controls > Managed Devices, set Access Type to Block All (least privilege), added all of my devices (under Allowed Devices) and made sure they were Always Allowed.
    4. I enabled Parental Controls > Managed Services, marked all my machines as Trusted and verified there were no blocked services out the box.
  • The Port Fowarding primer post, while great, doesn't cover this specific problem or mention Parental Controls like the bullet post in the bullet above.
  • I'm not a networking expert, but I like to think I know a little something.  I came from FiOS (which rocked by the way) and had no problem setting up these rules on their MI424WR.  I also did the same on my Linksys WRT350N before & after flashing DDWRT.
Regular Visitor

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

On 11/29 or 11/30, I reached out to Comcast & opened a ticket on this issue.

I spoke with some folks who troubleshot it for a while but they didn't conceptually understand the problem.  God bless them, they were reading from some documentation and using an emulator and didn't know what to do when it didn't behave the way it was expected to.  They left the ticket open, CR415275250 and invited me to call back for further troubleshooting.

 

 

This evening (12/3) I initiated a chat with Comcast Support via the website and got connected to John.  I briefly summarized the issue he said:

John: Julius, for your this issue please contact our higher fix team : 855-308-9452 or 855-308-9453

 

So I asked for updates on the existing ticket:
     JULIUS_: Any new notes in the ticket I referenced: CR415275250
     John: Julius, upon checking and verifying the ticket number that you've provided me I see here that the ticket is still open.
     JULIUS_: Ok.
     John: For your port forward issue, the best resolution is to call our higher fix team they have the access and will help you with your port forward issue.

 

Mean while, I had already dialed the number John provided & got to R. after a short wait (maybe 7-10 minutes).

After validating I was who I was, I gave R. the ticket number but R. said he couldn't find any open tickets with me.
I was still on with John in the chat so I told him:
     JULIUS_: The gentleman I spoke with said there was no ticket
     John: You're most welcome, Julius. Have a good evening.
     John: Oh I see, may be he missed the ticket number.
     John: I've verified the ticket and I saw it here on our system.

 

R, the Higher Fix Customer Associate (whatever his title is), asked me what the issue was.
I began by stating I was having trouble with Port Forwarding and R. immediately interrupted me right after 'Port Forward' saying, and I'm paraphrasing here, that Comcast wasn't responsible for the configuration or support of the device itself.

 

This is a somewhat foreign concept to me.

Its branded (physically and in the firmware) with Xfinity and the firmware and it came from Comcast.

Verizon gives its FiOS customers ActionTec routers and Verizon supports the device itself including customizations to a certain degree of course.

This to me of course makes sense: Verizon gave it to me, its running Verizon's customized firwmare to Verizon's specifications etc..

 

So R. told me to call the manufacturer of the device.  I sort of reconfirmed that even though it was an Comcast xfinity device that I'm renting, Comcast's support of the device is limited.  R. agreed with the statement and added that Comcast doesn't have the device so they don't know it and thus can't support it.  R. summed it up with something like: They [Comcast] didn't make it.  R. gave me Cisco's support number, 1-800-553-2447 and yet another ticket: CR416423930

 

Before hanging up, I asked where Comcast's support for the device ended and where Cisco's begins, and R.'s response could be boiled down to simply: If there's a red light, we know something's wrong.  If its green, everything should be ok.

*sigh*

 

 

After reeling back from my disbelief, I called the higher fix team again and got Michelle.  It took a little searching but Michelle was able to locate my orignal ticket and read the notes.  (So what happened before?)

She reconfirmed what the issue was and I briefly explained.  She said she would connect to my router and take a look.  (Again, what happened before?)

I asked her to talk me through the rule creation process but it failed.  I reconfirmed all the settings on screen, the process I was following and the information I was putting into the fields, and she acknowledged that everything I was doing and entering was ok.

 

Since she was connected to my device, and looking at that screen anyway, I asked her if she would be willing to try to create the rule for me.  She happily agreed, tried but low & behold it failed, returning the same 'Alert Failure! Please check input' error.  She was puzzled because as far as she knows, there's nothing inherently wrong with what we're doing.  She put me on hold a few times while she worked on this, presumably with a colleague or checking some documentation.

 

After 42 minutes on the call, they admitted defeat and escalated this to "the IT guys" (that's exactly what she said lol) who are the real technical folks who deal with hardware etc..  She linked the previous ticket to this one and assured me that its been escalated to another team as it may be an issue with the device itself.  When I asked if I could factory reset it, she said it's fine to do that, but not too often, because you don't know the devices history.  It could be a refurbished unit so who knows.

Interesting.

 

Before we parted ways, I asked her if I was doing anything unusual, or wrong or straying away from the norm.  She chucked saying no, I was absolutely not doing anything unusual and I've even gone above and beyond with trying to resolve the problem.  Good to know

 

Holding my breath.

New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

Just wanted to let you know I have the exact same problem.  Port forwarding used to work and now it isn't.  I have been able to sometimes get a port to forward by the following:

 

Reboot modem.

Setup a rule (I got no errors but saw no rules in the list.)

Reboot modem.

Now I see my rule and it works.

 

It seems once you get the error "check your inputs" that the only way you can do anything again is to reboot.

 

Right now I have a port forwarding like it should but I cannot see the rule.  I want to delete the forwarding so I guess I'll try to reboot.   I wonder if a recent firmware update broke this...?

 

 

New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

I am having this same issue, and I'm really leaning towards the idea of this being a faulty firmware update. Doing various Google searches, the only results I get that sound anything like what you are describing were posted within the last 3 months. It also seems that the router gives us no easy way to manually flash a firmware update. I would really like to hear more from Comcast on what we can do and who we can contact to resolve this.

New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

Put me down as another victim.  Trying to see if there's anything I can do about this... at the least, for the moment, going to try to work around with the DMZ settings, and see if that does anything.

New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

Just submitted a ticket for this SAME EXACT REASON, and to no surprise the comcast rep was unable to help. Awesome. 

New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

Yep, same here...my port forard config disappeared too.  Now I get, "Failure! Please check your inputs."

New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

Shockingly, not four hours ago, I went to change my port forwarding... and it was all back as it had been. Perhaps an update is being pushed out?
New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

I seem to have it fixed...here is what I did.  Go to Troubleshooting -> Reset/Restore Gateway and click on Restore Factory Settings.  I was able to add port forwarding and then I rebooted to check and make sure it was still there and it was.  Cheers and good luck.

New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

Troubleshooting -> Reset Gateway.  Come back to router console and the forwarded port will show.

 

In fact  a System Bug.

 

Way out of the league for Comcast support.  Sorry guys, but it's true.

New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

i had same problem. Resetting the gateway worked, thank you!  Hope it won't come back again.

New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

Guys! Are you using Wireless Gateway 3? I have the same problem too.

 

New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

I'm having the exact same issue with my router.  I have not been able to get port forwarding to work on the DPC3939.  I am not doing anything different on setting up the rules that I haven't done before over the last 7 years with other routers.  It just won't work. 

I then had the problem with my "services" vanishing.  I would get the error about checking the inputs when trying to re-create a rule/service in port forwarding that I had previously setup.  It would appear I could create a new rule with different parameters, but as soon as I would navigate away and back to the port forwarding screen, the entry would be gone. 

 

I finally did a factory reset on my router today and I can add and see the services I enter in port forwarding, but despite the entries showing in the table, port forwarding still does not work.  My kids can no longer play multiplayer games with their friends, nor can I ever since getting the DPC3939 router.  I shouldn't have to go buy another router to place in bridge mode just to be able to do something basic and common like port forwarding.

New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

*sigh* First problem I ever had with Xfinity. Still doesn't work about half a year later. No one can help and as said above, it is way out of their league.

New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

I had the same issue and looks like its related to the browser.

Try CHROME and you will be just fine.

I had this issue on IE

Try CHROME and you will be just fine.

New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

Browser is irrelevant.

 

Just posting as another person with port forwarding issues from Comcast.  I had exact same experience as MWilson.  For what its worth, I had a spare Netgear router so hooked it up and went into Bridge Mode.  I have my port forwarding rules set up on it, and they still don't work.  Comcast is doing something that is specifically blocking ports and their tech support are totally and completely unable to help or even understand or acknowledge the issue.  This is beyond frustrating!!

New Poster

Re: Port Forwarding Rules Vanish; New Results in Failure! Please check your inputs.

Just got off the phone with their top tear support...would you believe the agent was searching google to help me!!!...seriosuly?! Port Forwarding that complex??

It's pretty forward if you ask me(pun intended)

 

I had to explain to her...serioulsy??...she kept thinking I was having internet issues....omg

 

I give up. Thank you comcast for wasting 3 days of my life and never commenting on this thread or educating your support on how to help with this issue. Thanks for telling me I have to now talk to your business dept. JUST to get help with forwarding my ports amazing!!!!!!