Question Can ping but can't browse

[RustyTheCat]

I am having an unusual problem while trying to set up my Internet. I have tried many different solutions, but have not had any success so far.

Hardware:
-Modem: Motorola mb7220
-Router: Linksys EA6900 V1.1

Problem:
The modem has connection to the internet. I can successfully ping and tracert to google.com, however whenever I try to use a web browser to access a website I receive "Unable to connect" or sometimes a 403 error.

The problem occurs on all devices, and the results have been the same whether I go through the router or simply connect directly to the modem via ethernet cable.

So far I have tried:

• power cycling all devices involved
• releasing and renewing the ip address
• clearing the DNS resolver cache
• changing the mac address of the router
• manually changing the MTU on the router
• factory reseting both modem and router
• updating firmware on router
• restarting winsock service
• clearing the cache/cookies of the browsers

Any ideas would be greatly appreciated. I have now spent most of today and last night trying to debug this issue, and it seems I have exhausted all related solutions I could find online.

Update:
After some more testing, I used telnet to determine that regardless of what my browsers are showing me, I am getting a 403 error from every single website. Again this is the same from every device.

 

[Math Geek]

can you get to a site using it's IP address and not domain name? sounds like a DNS issue to me at first read.

check your IPv4 settings to ensure it is set to get DNS through the DHCP. sometimes this setting can get changed. you can also try to manually change it to another DNS service. like maybe google's 8.8.8.8 dns server.

 

[ElectrO_90]

News.bbc.co.uk = 212.58.249.145
Can you put that IP in your browser and does it work or not?
If it does, it should be as Math Geek said and a DNS problem
If it doesn't its being blocked at a port level. eg malware/spyware, virus, firewall

 

[RustyTheCat]

It is not a DNS issue. I can perform nslookup on google.com, but when I enter that IP into the browser I still get a 403 error.

I also do not believe it to be a malware/virus problem as the problem occurs on the whole network regardless of what device is being used. It also still occurs if I connect directly to the modem.

I wonder if it could be that the public IP assigned to me is blacklisted. However, this doesn't quite make sense to me as I have not found a single url that gives a different response than 403. I also do not know of any way to get my public IP without using one of the "what is my IP?" websites as they too return 403 errors regardless of whether I try to access them via browsers or the command line.

 

[ElectrO_90]

Maybe you can use a VPN
Or best yet, phone up your ISP

 

[RustyTheCat]

Is there any way to verify that this is actually the issue though? I have already tried going through my ISP (Comcast) for help several times and every time they have run out of potential solutions (even after elevating me to their "advanced repair" team).

I also believe that Comcast uses dynamic IP allocation based on the MAC address of the router, so disconnecting my modem and manually changing the MAC address of the router should get me assigned a new IP address in their system (which I have already tried several times). They do not seem to have a way to manually reassign me an IP address on their end.

I could confirm that this is the issue if I had a way to find my public IP address so that I could look up if it is blacklisted, however I have not found how to do this without simply getting a 403 error.

 

[Math Geek]

if it is not DNS, then it has to be something with the ISP end of it. have they tried swapping out the modem for another and see if that helps? could be something within the modem itself that is not working. they often hand out used equipment and it's possible you just got a messed up modem.

obviously it's not the router as skipping it does not help. it's time to really get an attitude with comcast until they come out and fix it. or cancel them and get another service if they won't help.