Error 645 when trying to connect to Internet

I have a PC that has two partition win98 and Win2k server.

When using win 98 I am not able to connect to internet.
After dialing(with all the handshake sound) I will get this error Error 645, The Microsoft Dial-up adapter is not installed or not reponding properly. In the network section of control panel, remove the driver and then add it again.

I have tried reformatting this partition but I still get the same problem....

Please help....
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gemartiConnect With a Mentor Commented:
Maybe you don't have the most recent version of DUN installed?

When you say removed the driver and reinstalled, do you mean that you have reinstalled the dialup adaptor and its tcp/ip protocol in ControlPanel/Network.

Have you also tried reinstalling your modem driver??
fkmfkmAuthor Commented:
Yes i have tried removing it and adding it again...I have also reformatted the whole partition twice...
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In the properties of you dialup connection, make usre that "require encrypted password" is not checked
also make triple sure that your username and password are typed in correctly
also make usre you have tcp/ip installed on this machine
fkmfkmAuthor Commented:
stevenlewis: everything is correct , the default one after win98 setup.

gemarti: what is DUN ?
fkmfkmAuthor Commented:

Oic Dial-up do i check what DUN do I have and how do I update it ?
fkmfkm, I work for an isp, and we require that some configuration of the dialup is required. check your w2k dialup, and make sure they both are the same
fkmfkmAuthor Commented:
I will check, but as far as I remember, everything is default....

Actually it worked before (with the win98 version that came with my new pc).

But after I formatted it using my own win98 it dont work anymore.(but this version works on my old pc)

Please help
fkmfkmAuthor Commented:
I will check, but as far as I remember, everything is default....

Actually it worked before (with the win98 version that came with my new pc).

But after I formatted it using my own win98 it dont work anymore.(but this version works on my old pc)

Please help
Don ThomsonCommented:
In Control PAnel  - under Modems  - Diagnostic Tab   - Click on the Modem and then More info  - do you get AT responses in the box?
Boot up into safe mode (F8 after memory run and before windows splash screen.)
Then go to control panel  |  system | device manager and remove all under modem and network adapters.
Now reboot and when you come back into windows it should reinstall - then check device manager again to see if all is working properly (I had the reverse problem of modem not working properly on w2K pro!)
Do try Shekerra's advice, but IMHO do one thing more:
Before rebooting go into start | control panel | add/remove programs | windows setup and navigate to accessories communication and uncheck dial up networking.
After rebooting where windows will install your modem, do it again, but this time check the dialup networking to reinstall the dialup networking items. (dialup adapter, TCP/IP)
fkmfkmAuthor Commented:
DTHConsulting. my modem is ok..the handshaking all ok..i is just before the TCP Connection it fails..

Shekerra, tonnybrandt..I will try it when i reach home u all have the same problem ?

Thank you.
fkmfkmAuthor Commented:
Has it got do do with the version of win98...? cause my version is quite old..and my new machine is ASUS A7A266 Athlon 1.4 ???
I have this problem w/ windows 2000 - I just have not had time to fix it yet!
Some other MS articles that deal with the "Error 645"
Err Msg: Error 645 Received When Connecting to MSN

Cannot Connect to H/PC and Virtual Private Network at Same Time

Routing and Remote Access Server Stops Authenticating Dial-Up Networking Clients

00582: Error 645 - Internal Authentication Error
Runtime error 645 can be caused by a number of things. It can be a conflict with other programs on your system, a generic Dial-Up Networking (DUN) error caused by Password List problems, or a corrupted installation of DUN. The cause can vary greatly so we must begin troubleshooting the problem, starting with the easiest causes first.
Configuring the Windows 9x Network Components for DUN
     Note: These instructions assume that the machine being configured is NOT connected to a local area network (LAN). If you are and follow these instructions you may create a conflict which interrupts your computer's connection to your LAN. Please ask your network administrator for assistance before making any changes to the system configuration.

1. Click on Start > Settings > Control Panel > Network.
2. What you will find you will depend upon your version of Windows. We need three components total, but you may have more or less listed. The three we need are
 Client for Microsoft Networks
 Dial-Up Adapter
3. If TCP/IP is not listed, we will have to add it:
  1. Click Add
  2. Double click on Protocol
  3. Hilight Microsoft on the left
  4. Double click on TCP/IP on the right to add it to the list.
4. If Client for Microsoft Network is not listed :
  1. Click Add
  2. Double click on Client
  3. Hilight Microsoft on the left
  4. Double-click on Client for Microsoft Networks on the right to add it to the list
  5. We should now have at least the three components we need.
        Note: If you have any others and do not need them, start at the top, then hilight them one by one and click Remove until you only have the three listed above.
6. We now need to ensure that TCP/IP is properly configured.
  1. Select TCP/IP and click Properties
  2. If given a warning about changing TCP/IP properties, click OK
  3. On the IP Addresses tab "Obtain an IP address automatically" should be selected
  4. On the Wins tab, make sure it is set to Disable
  5. On the Gateway, remove any installed gateways
  6. On the DNS tab, make sure it is set to Disable as well
  7. Click OK
7. Next we will need to setup this computers identity.
     (you may be able to skip this step if you already entered a computer name)
Select the Identification tab at the top of the Network properties window. We will want to change the entry here for Computer Name.
For simplicity, make the name between 4 and 8 characters (letters and numbers only), preferably all lower case letters, example:
Computer Name: brewer
 Workgroup: workgroup
Computer Descr: brewer
8. Click Ok
You may now be prompted for the Windows CD-Rom, or the file copy may begin automatically. If  prompted for the Windows CD, insert the CD and click OK. If you are still prompted for it after clicking OK, verify that the drive letter listed in "Copy files from" is your CD-Rom drive.
                  Note: If at any time during the File Copy you are given a warning about "Version Conflict" or any message "A file being copied is older", click NO to each and every message you see like that. If it prompts you that the file is not found, the CD drive letter is either incorrect, or you are not using the CD-rom that was used to install Windows on your computer.
If you have made any changes, or added any components you will be prompted to restart, click YES. When Windows restarts, you may see a dialog box asking for a Username and Password to login. For Username, enter in the same name you did for Computer Name in the prior step, entering it in the same all lower case format. Do not enter a Password.Then click OK. If asked  to confirm, click OK.
Reinstall D.U.N.
1.Ensure you have the original Windows 98 CD  and that it is the correct version (i.e. the version that installed Windows 98 on that machine).
2.If your computer is on a LAN (local area network) please refer to your Network Administrator before continuing.
3.Click Start, Settings, then Control Panel.
4.Double click Add/ Remove.
5.Click the Windows Setup tab.
6.Double click  Communications.
7.Untick the Dial-Up Networking box.
8.Click OK.
9.Click OK again.
10.This takes you back to the Control Panel. If you are prompted to restart select Yes.
11.Shut down and restart the computer.
12.After the computer has restarted, go back to the Control Panel.
13.Double click Add/ Remove.
14.Click the Windows Setup tab.
15.Double click on Communications.
16.Tick the Dial-Up Networking box.
17.Click OK.
18.Click OK again.
19.Windows will prompt for the CD ROM or disk and begin copying files.
20.If a Version Conflict dialog box appears during copying, it will ask you if you wish to keep the existing file or not. You should select No to all these questions. This is because selecting Yes will not overwrite any files, which will not be a clean reinstallation.
had similar prob.......potentially easy fix try this
goto C:\program files\internet explorer\signup... click 'signup'
this will (hopefully) get you to your isp and autofix the settings...........
As advised above try the latest DUN update, Dun 1.4 upgrades
fkmfkmAuthor Commented:
I have installed win Me based on you suggestion...and it works...probably my win98 is too old

Since you are the first one to mention this ...i give u the points...

Thanks. Sorry I didn't answer your question about DUN. I got Sidetracked and had never actually finished my response. I was going to give you a link to update DUN.


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