Resolved Internet keeps diconnectiong at random times in Win7

I have a LAN with two computers connected to a Dlink router that in turn connects to a DSL modem to the internet (via phone cable). Normally, when I boot either or both up I can access the internet fine. BUT every once in a while one computer loses the connection and I can no longer surf via browser or get my mail. If I open a command prompt and type "ipconfig" it normally shows:

===
===
Windows IP Configuration


Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . :
Link-local IPv6 Address . . . . . : fe80::45b6:7ad0:8dd0:2135%11
IPv4 Address. . . . . . . . . . . : 192.168.0.101
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.0.1

Tunnel adapter isatap.{4B465585-FEAB-42F3-B02A-362AC721AF01}:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :

Tunnel adapter Teredo Tunneling Pseudo-Interface:

Connection-specific DNS Suffix . :
IPv6 Address. . . . . . . . . . . : 2001:0:9d38:6abd:ce2:13ff:ba62:51d6
Link-local IPv6 Address . . . . . : fe80::ce2:13ff:ba62:51d6%13
Default Gateway . . . . . . . . . : ::
===
===

BUT if I do it now when the internet is inaccessible on this PC, the "Tunnel adapter Teredo Tunneling Pseudo-Interface:" at the bottom now says it's disconnected (and internet no longer works):

i.e.:
===
===
Tunnel adapter Teredo Tunneling Pseudo-Interface:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
===
===


I have to end up rebooting the computer 3 or 4 times for it to finally get the connection back. WHY would this happen? The cable connection to the Dlink router is fine because I can see the other computer and read from it fine through the lan. AND the other computer connects to the internet fine and its "Tunnel adapter Teredo Tunneling Pseudo-Interface" shows values (does not say media disconnected). ONLY this computer drops that connection and won't let me browse or get email at random times (not always, but often enough to be a nuisance). I'm not even sure what to look into as I am using a brand new ethernet cable and again can access the other computer fine on the lan, only this computer's connection for "Tunnel adapter Teredo Tunneling Pseudo-Interface" keeps disconnecting and thus the internet access.

 

Hmm .. why is it that when IP6 isn't connected I can't get to the internet then?

 

Hmm that's strange because the other PC on the network has the same setup and it works fine, never disconnects. Also this disconnecting only started happening sporadically past few months, wasn't a problem before and I've had this setup for years.


Here's what that site gave back:

SUMMARY tab:
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Your IPv4 address on the public Internet appears to be <address suppressed>

Your Internet Service Provider (ISP) appears to be BACOM - Bell Canada,CA

No IPv6 address detected [more info]

Good news! Your current configuration will continue to work as web sites enable IPv6.

You appear to be able to browse the IPv4 Internet only. You will not be able to reach IPv6-only sites.

Your DNS server (possibly run by your ISP) appears to have IPv6 Internet access.
===

TESTS RUN tab:
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Test with IPv4 DNS record
ok (0.177s) using ipv4
Test with IPv6 DNS record
bad (0.075s)
Test with Dual Stack DNS record
ok (0.425s) using ipv4
Test for Dual Stack DNS and large packet
ok (0.405s) using ipv4
Test IPv4 without DNS
ok (0.344s) using ipv4
Test IPv6 without DNS
timeout (15.070s)
Test IPv6 large packet
bad (0.064s)
Test if your ISP's DNS server uses IPv6
ok (1.281s) using ipv4
Find IPv4 Service Provider
ok (0.547s) using ipv4 ASN 577
Find IPv6 Service Provider
bad (0.206s)
===


One of the results from that site is "Your DNS server (possibly run by your ISP) appears to have IPv6 Internet access." but the other results seem to say I'm not setup to use it. Is there something specific I need to configure should I need access to IPv6 sites either now or later?


Also,
I'm still confused as to why when IPCONFIG gives back an address, i.e.:
--
Tunnel adapter Teredo Tunneling Pseudo-Interface:

Connection-specific DNS Suffix . :
IPv6 Address. . . . . . . . . . . : 2001:0:9d38:6ab8:3c9b:c6f:ba62:51d6
Link-local IPv6 Address . . . . . : fe80::3c9b:c6f:ba62:51d6%13
Default Gateway . . . . . . . . . : ::
--

the internet works fine on this machine, but when it doesn't IPCONFIG displays:
--
Tunnel adapter Teredo Tunneling Pseudo-Interface:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
--


If IPv6 isn't working/setup then why does it give back an address, in this case "IPv6 Address. . . . . . . . . . . : 2001:0:9d38:6ab8:3c9b:c6f:ba62:51d6" and the site you linked says it can't find an address assigned to IPv6? IPCONFIG displays an address for it and the site says there isn't one assigned?

I guess I'll have to contact Bell and get them to explain how they are dealing with IPv6 and if anyone else is having these issues.

 

Sorry I don't feel you know what you're talking about, it's only when IPv6 IS connected that my internet works so disconnecting it makes no sense. No matter things are working now consistently and I changed nothing. Go figure.