Solved: Problem with switching back to dynamic IP - My other computers cannot see network now

[kelticvixen]

Hello! After struggling for several hours on my own, I've decided to seek help on my networking problem. I will run down what caused the problem (aside from my own cluelessness) and the order of events. I have several screenshots I will post for the sake of clarity. My system specs are listed in my signature below. Dxdiag attachment is included if needed.

Current Problem:
a) My computer can only get online now if I input a static IP. Switching back to Dynamic IP setting gives me the Vista "unidentified network" error (I am still not very familiar with Vista as my computer is new).

b) My other two computers cannot get online at all now (much to my husband and daughter's discontent), whereas before I changed my ip to a static address they connected just fine.

_______________________________________________________________________

Sequence of events:

Initially I had only two computers on my home internet network: one connected directly to my Linksys router via ethernet cable, and one connected via wireless ethernet card.

When I got my new computer, I hooked it up to the router also, with an ethernet cable. For a short, glorious time, all three computers co-habited in peaceful DSL connectivity.

To shorten the story at this point, I decided to change my IP address to a static IP so as to port forward for a program. When I ran cmd and entered ipconfig /all to write down my ip info (current ip address, subnet mask, default gateway and DNS servers) I happened to note that even with all of the musical chairs my computers went through when I switched out network cards and such the ip info was the same as I remembered it from times before when I had done port forwarding and switched to static ip addresses.

Next I proceeded to follow online instructions to change ip to static address in Vista: Manage Network Connections ->right click to get to properties of my connection ->then properties of TCP/IPv4 ->change to static IP in the usual manner. I tested my connection and found that it worked perfectly.

Sadly, after this my other computers suddenly were unable to access the internet. My laptop from work, which had previously connected wirelessly with ease to my network, now showed an error which said something to the effect of "Unable to connect/Limited Connection". The other two computers with older OS's just refused to connect.

I figured right away that somehow in changing my ip to a static address I had changed "something", or caused some conflict that I didn't understand being a total Vista noob. I went back in and changed my settings back to autoconfigure. THIS caused my own computer not to connect at all now. I received my very first look the now dreaded "Unidentified Network" error message (see below for screenshot). This has perplexed me because obviously before I changed my ip to static, it had been dynamic and I connected great, and so did all of my other pet computers. So at this point no one could connect. I ran cmd again, and ipconfig /all and noticed that my dynamic settings were totally different from what I remember. A different dynamic ip, a different subnet mask, and no default gateway at all (see below for screenshot). Prior to this even with my ip set to autoconfigure it always used to be the same one.

Needing to connect to the internet to surf for solutions, I again set my ip to a static address and viola instant connection. But I am still left unable to figure out how to reconnect my other computers to the network, as they no longer seem to see the network, even though the signal is there. Also it seems that I should be able to choose to set my ip to autoconfigure for a dynamic ip address AND still be able to connect to the internet. I am extremely perplexed.

Here are some screenshots... I tried to sort of eliminate actual ip info, while still showing the different settings. Please let me know if I scratched out something that needs to be shown.

After switching back to a dynamic ip setting I get this error:

This is what the dynamic autoconfigure setting looks like when you run cmd and ipconfig /all:

This shows where I set it to static ip and ran cmd prompt and ipconfig /all:

Sorry this is so long...I wanted to be as clear as possible in my explanation and request for help. Any assistance would be greatly appreciated! Thanks in advance.

 

[zx10guy]

Well, first, you can't reuse the same IP you had when you had your PC set to autoconfigure which is the new fangled Vista way of saying DHCP enabled. The reason you can't reuse that IP is because your router is acting as the DHCP server which issues IPs to PCs configured to operate under DHCP. What proabably happened was when you set your PC to use the IP you got under DHCP or autoconfigure as a static address, one of your PCs obtained an IP from your router which happened to be the same IP as your PC. You can't use IPs set in the address range in your router for DHCP requests. You have to use an IP outside of that range or you have to set up exclusion addresses so the DHCP server in your router knows not to issue those IPs for requests.

The first ipconfig/all screen shot tells me that when you set your PC up to autoconfigure, you didn't get an IP from your router for some reason. How do I know? Well, there's enough of the numeric of the IP showing despite the blank out you put in to tell me the first octet of the address is 169. Anytime you get a 169 address under Windows, that tells me there was a DHCP issue where Windows was unable to get an IP from a DHCP server.

 

[JohnWill]

There is no security risk in showing private IP addresses, and you're obscuring valuable troubleshooting information by doing so.

Let's start with some basic information.

Please supply the following info, exact make and models of the equipment please.

What country are you located in.
Name of your ISP (Internet Service Provider).
Make and exact model of the broadband modem.
Make and exact model of the router (if a separate unit).
Model numbers can usually be obtained from the label on the device.
If wireless, encryption used, (none, WEP, WPA, or WPA2)
Version and patch level of Windows on all affected machines, i.e. XP-Home (or XP-Pro), SP1-SP2, Vista, etc.


First off, you should reset all the machines to dynamic IP addresses again. Then turn off EVERYTHING, router, modem, and all the computers.

1. Turn on the modem, wait for it to initialize for a couple of minutes.
2. Turn on the router, wait a couple of minutes for it to boot and connect to the modem.
3. Boot the computers one at a time.

Now, please post this for each of the three computers.

Hold the Windows key and press R, then type CMD to open a command prompt:

Type the following command:

IPCONFIG /ALL

Right click in the command window and choose Select All, then hit Enter.
Paste the results in a message here.

If you are on a machine with no network connection, use a floppy, USB disk, or a CD-RW disk to transfer a text file with the information to allow pasting it here.

 

[kelticvixen]

Thanks for the replies! zx10guy, you are absolutely right about the ip starting with "169". This is also the case on my daughter's computer, though the one my husband is using still looks like it used to (192.168.1.102). What might be causing this? Something on my router settings? I didn't change anything on my router except for the port forwarding.

JohnWill- I very much appreciate the suggestion, and I am about to try it after posting this. I have changed the pictures on my original post so that all info is readily available. I wasn't sure about the ip addresses being a security risk and I thank you for enlightening me on that.

Here is the info you requested: Currently there are three computers, including mine, which were permanently and happily connected to the router. Two of them are sad old fogies, used only for surfing or other minor apps, so try not to laugh too hard when you see the OS's and such. The other "good" computer died a month ago which is why I got my new pretty machine. I am not including my office laptop at the moment, but if necessary I will. It's packed up at the moment. Suffice it to say, that prior to all this it connected fine as well, wirelessly.

Country: USA
ISP: Windstream
Make and Model of Broadband Modem: Speedstream 5200 Ethernet USB ADSL modem; Part # 060-E242-A13
Make and Model of Router: Linksys Wireless-G (2.4 GHz, 54 Mbps) Broadband Router, Model WRT54G Ver. 2 (Four Port Switch)
Security Wep: Disabled
The Computers:

My computer: (the cause of all the mess up): Windows Vista Home Premium (6.0, Build 6000)
Current ip address: (static in order to post this since I can't connect online at the moment with dynamic) 192.168.1.136 ***I had set it to this address when instructed to during port forwarding procedures, but I can also get online if I set the static address to my OLD, DYNAMIC address of 192.168.1.101*** (please note that my husbands is still 192.168.1.102 and it is just mine that won't go back to it's previous dynamic address, maybe due to Vista's handling of DCHP as zx10guy mentioned? Regardless, I don't know enough about Vista OR DCHP to speculate.)
Subnet Mask: 255.255.255.0 (I noticed that the other computers display wacky looking -to me- Subnet Mask addresses)
Default Gateway: 192.168.1.1
DNS Servers: 192.168.254.254

Joey's computer: Microsoft Windows 98 4.10 Build 2222
Current ip address: 192.168.1.102
Subnet Mask: 255.0.0.0
Default Gateway: 192.168.1.1
DHCP Server: 192.168.1.1
DNS Server: 192.168.254.254

Sarah's Computer: Microsoft Windows 2000 Pro 5.0 Build 2195
Current ip address: 169.254.107.20
Subnet Mask: 255.255.0.0
(that is all ipconfig /all showed on her cmd screen)

I hope I got everything. Please let me know if you need additional info and thanks again very much for your gracious assistance in this quandry of mine! I will now commence testing out your above referenced suggestion in restoring dynamic ip addresses and shutting down. I will return with results.

 

[TerryNet]

If the Windows 98 is getting a dynamic IP configuration the router is messed up or confused. Try a reset to factory default settings and see what happens. If it's static, fix the Mask (255.255.255.0).

Is the router's Dhcp server enabled?

For the Win 2k Pro and the Vista please show the complete ipconfig /all per John's request. You'd be amazed at how many problems he's been able to quickly fix after seeing the complete info.

 

[zx10guy]

DHCP or dynamic host configuration protocol is a way to cut down on administration headaches. You just set all the relevant IP information for the network in one place which is the DHCP server. The clients or workstations set to work under DHCP just do a general broadcast to request an IP from the DHCP server. When the DHCP server sees this request, it then replies back with the appropriate information to the requesting client. The DHCP server then notes that it already has handed off this IP and knows not to reissue this IP when it receives the next request.

With that said, it's hard to see what's going on here. Usually DHCP just works except when you have something a bit more complicated where the DHCP server is not on the local network and is routed. One suggestion might be to reboot your router to see if this helps fix things. There shouldn't be anything unique about how Vista works with DHCP except things that were intuitive for me to navigate around in XP are just a chore to find under Vista. One other thing, the lone computer with the 192 address, can it work normally on the internet? Because the DNS IP I'm seeing does not look correct. Usually, it's the IP of the router which in this case is 192.168.1.1.

 

[kelticvixen]

If the Windows 98 is getting a dynamic IP configuration the router is messed up or confused. Try a reset to factory default settings and see what happens. If it's static, fix the Mask (255.255.255.0).

Is the router's Dhcp server enabled?

For the Win 2k Pro and the Vista please show the complete ipconfig /all per John's request. You'd be amazed at how many problems he's been able to quickly fix after seeing the complete info.

Hi there! Ok well the first suggestion didn't work, unfortunately. None of them can connect, and my ipconfig /all is the same with the first 3 numbers of the address being "169". The 98 computer is set to dynamic, and I don't know why the subnet masks are showing up with the extra zeros. I will definitely try resetting the router to factory default settings...I'll report back on that in a minute too. I do know that the router is set to DHCP enabled.

Aside from printscreen, which I did for Vista's ipconfig /all, how do I show the complete page for ipconfig /all? Printscreen only shows as much as I posted.

Thanks for the advice!

zx10guy: I appreciate the explanation of DHCP, although I will have to read it a few more times to actually comprehend. I am so thick about networking! As to your question about the lone computer with the 192 address, no it cannot connect on it's own. Last night I went so far as to completely uninstall my ethernet adaptor and driver from the Vista computer and even with it shut down the other computers could not connect.

Previous to this current problem, my DNS server was always 192.168.254.254 and my default gateway would be the one with 192.168.1.1

Thanks very much for your help! I am surely in need of it.

 

[zx10guy]

Just to appease me, set the DNS server IP on the computer with the 192 address to 192.168.1.1 and see if it can pull up any web pages.

 

[kelticvixen]

Just to appease me, set the DNS server IP on the computer with the 192 address to 192.168.1.1 and see if it can pull up any web pages.

I'd probably do anything to appease you right now because I'm so happy! TerryNet's suggestion to reset the router to factory default settings seems to have done the trick! All computers are connected, and I even upacked my office laptop and IT'S connected too!

Just so you can have closure on this, I am checking the lone computer's address (the one you mentioned with the (192) to see what it currently is.

Oh and I'll post a happy new screenshot of my dynamic ipconfig /all success from my Vista computer!

Here is the lone computer (the win98) ip now: dynamic ip: 192.168.1.101
Subnet Mask: 255.255.255.0 (Yay!!)
Default Gateway: 192.168.1.1
DHCP Server: 192.168.1.1
DNS Server: 192.168.254.254

It only took me a total of 4 hours and 45 minutes to accomplish this lol. I'm still not sure what went wrong in the first place, but the router seems to have been "confused" as I think TerryNet mentioned.

Thanks again for the wonderful patience and assistance! THIS is why I recommend this forum to my friends, and why it's the only place I ever go when I have tech support questions. Thanks!!

Here is my dynamic ipconfig /all screen NOW:

 

[TerryNet]

Great!

Just to try for closure on two things ...

kelticvixen, the clue to posting the entire Command Prompt window is in these lines from the end of John's post, with the most important parts bolded:

"Right click in the command window and choose Select All, then hit Enter.
Paste the results in a message here.

If you are on a machine with no network connection, use a floppy, USB disk, or a CD-RW disk to transfer a text file with the information to allow pasting it here."

zx10guy, would it help if I said that the "modem" is a modem/router with LAN IP 192.168.254.254? And that the second router is getting that as its WAN DNS and passing it on to the computers?

 

[zx10guy]

Great!

Just to try for closure on two things ...

kelticvixen, the clue to posting the entire Command Prompt window is in these lines from the end of John's post, with the most important parts bolded:

"Right click in the command window and choose Select All, then hit Enter.
Paste the results in a message here.

If you are on a machine with no network connection, use a floppy, USB disk, or a CD-RW disk to transfer a text file with the information to allow pasting it here."

zx10guy, would it help if I said that the "modem" is a modem/router with LAN IP 192.168.254.254? And that the second router is getting that as its WAN DNS and passing it on to the computers?

That's what I was thinking was happening too. Usually, I see as a standard configuration, the DNS server as the router itself. But hey, what ever works.

 

[kelticvixen]

Great!

Just to try for closure on two things ...

kelticvixen, the clue to posting the entire Command Prompt window is in these lines from the end of John's post, with the most important parts bolded:

"Right click in the command window and choose Select All, then hit Enter.
Paste the results in a message here.

If you are on a machine with no network connection, use a floppy, USB disk, or a CD-RW disk to transfer a text file with the information to allow pasting it here."

Ahhh! I completely missed that lol. Many apologies, and I've learned something new. Thanks again!