Working External Modem Will Not Connect

I have an external Agre modem in which was working this morning and now fails to connect to the internet on either one of my drives.

I have an identical modem on another computer that I know works and it too will not work on this machine. I have looked at ports and queried the modem and all I get from a query is that the modem has failed - even on the modem I know is working. The phone line is also working. I also tried a restore point to no avail,

I checked my settings on my ISP (dial up) connections to make sure a setting on any one of them might have slipped off for some reason.

So my theory is that I have a working modem but a dial up connection that will not even allow the modem to work (no dialing sounds) and the port is intact (I even changed ports and there are no conflicts)

Does anyone have the foggest idea what has happened? I have no error messages other than the one that the modem has failed.
Who is Participating?
giltjrConnect With a Mentor Commented:
I have no problem with getting no points.  However, if you feel you want to award me some, I do beleive you can award partial points and ask the rest to be refunded.  I am not sure how to do  this, I am sure there is a FAQ about it.

I glad to see its working.  By chance did you have the PC  powered down for a long time?  If so, this could have been the resolution.  Since most things are Plug-and-Pray, opps I mean Play, I have seen them change the order they are defined to the system at power up time after being powered down for a few days or weeks.
How does the modem connect to the computer?  Serial or USB?

If querying the modem fails, then it seems like the connection between the computer and the modem has failed.
HMCSAuthor Commented:
it is a serial connection - I have another connector from the other computer - I coud (with some difficulty) switch them out
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HMCSAuthor Commented:
I have used another cord AND also the other identical modem -  still all I'm getting is that there was a modem failure and I know that is 100% impossible since the modem and connecting cable came off a computer that this combination worked.

Any ideas as to the problem? the modem will not connect or make any sound on ether of my 2 physical drives.
HMCSAuthor Commented:
Just to be DARN sure I took this identical working modem and connecting cable and installed it on a friend's machine. It worked perfectly. So it is my opinion that the malfunction lies in the computer either physically or in both O/S of this old computer.I have 2 physical drives with XP on each of them.

Any ideas ?
Sorry I didn't respond earlier.  I've been out of  town and did not have Internet access.

To me it sounds like the serial port is bad or the port is configured incorrect.  I would double check what the BIOS says the settings are for the serial port.  Make sure they match what the OS has.

Once you verify they are the same and if it still does not work, then I would try deleting/removing the serial port definition and re-add it.  

If that does not work, then it sounds like there is a physical problem with the serial port.  

When the modem is connected to the "bad" computer do any of the lights light up?  Short of a break out box there is no real way to verify the port is bad.
HMCSAuthor Commented:
I'll have to do some checking but them modem does "light up" when turned on but it might light up even if not connected - I really don't know.

As for the serial port in BIOS I don't really have the foggest what I'm looking for. I'm not into that part of computers very often. All I know is one morning it worked and that afternoon it was as dead as a mackerel

I can see how a port might become "bad" but how does one become incorrectly configured?

After I figure out what the BIOS says and then find out somehow what the computer itself says about the port - then I guess we can go from there cause I haven't the faintest idea about deleting a serial port. I doubt if I have more than one. The M/B is an Abit KG-7

Right now I'm struggling to get what was once a stand alone computer with vista working with the internet - since I like to have 2 internet working computers. I'm having more fun than I wanted.

During that morning I was working on another computer that is practically side by side with the one that is not working - I don't think I could have damaged the other computer but anything is possible

What lights does the modem have and what lights are on after the modem is powered up?

As for incorrectly configured, easy.  Way back in the DOS days (actually before DOS) each serial (a.k.a communication/COM) port had interrupt "code" (IRQ) that it would use to tell CPU it needed something  and a specific memory address to communicate with the CPU.  Originally there were 4 possible com ports they were:

     Com1, IRQ 4, address: 0x3F8
     Com2, IRQ 3, address: 0x2F8
     Com3, IRQ 4, address: 0x3E8
     Com4, IRQ 3, address: 0x2E8

All it takes is that either BIOS or the OS settings to be changed to something other than the above, or from what they were originally and the config is wrong.

In your BIOS there should be a "Intergrated Peripherals" options.  On that screen there is serial 1 and serial 2 configuration options.  You can check what the setting are.  The default for serial 1 should be 3F8/4 and for serial 2 is 2F8/3.

Since your MB has two serial ports, have you tried the second one?
HMCSAuthor Commented:
I don't know if the MB has a second serial port. I haven't looked. I stated that I doubted that I had more than one serial port.

The computer is unfortunately located in cramped quarters and must be turned  to view even remotely the back and to top this off I must be on my hands and knees to work on this and my other computer. My Vista computer is lucky to be on a table. Being on my hands and knees is a neat trick since I had a stroke 3.5 years ago and this makes movements like this on a need to basis. I can get on my knees fairly well but getting up is another matter entirely.

at any rate today I'll be looking into the BIOS, etc to hopefully determine the problem. I'll let you know.
HMCSAuthor Commented:
When the computer is off but the modem is on I have these lights lit up:


When the computer is powered up these lights, in addition to MR CS are lit up:


These lights are off:


Modem is on com 2 - was on com 3 till I changed it it an attempt to solve the problem. On com 4 is a non working internal modem which was hit with a power surge 1.5 years ago. I lost 2 modem in one day due to a freak storm in an otherwise drought ridden summer. This is why I have 2 identical modems.

When there is a dialing attempt there are no other lights lit up or blinking. I ave also checked my dial up connections - I have more than one. They seem to correspond to setting I have on my other working computers.

The modem will not query and looking at the modem log I see these 2 entries:

DSR is low while initializing modem, verify the modem is turned on
CTS is low while initializing modem.

Timed out waiting for response from modem
Failed to send command because of WriteFile Failure, error = 00003e3

This is all I have at the moment.

Brief explanation of the lights (at least what they normally mean):

     MR = Modem Ready (a.k.a DCE) = modem is ready to talk to the computer
     CS = Clear to Send - The modem is ready to receive data from the computer.  
     RS = Request to Send - the modem would like to send data to the computer
     SD = Send Data - the modem is sending data to the computer
     TR = Data Terminal Ready - the computer is ready to talk to the modem.
     CD = Carrier Detect, the modem has successfully connected to another modem.
     OH = Off Hook, the modem has "taken the phone off hook to make a call"
     RD = Receive Data, the Modem

Most modems today simulate a full duplex data connection (meaning the computer and the modem and send data at the same time).  So typically  MR/CS/RS/TR all all  high.  If you were using Half-Duplex, these would toggle on and off to control the flow so that either the computer was sending data to the modem or the modem was sending data to the computer.

CD is normally high all of the time these days also, when modems could not simulate full duplex telecommunications, this was  used to control data flow between the modems.

What is interesting is that if I understand things correctly you have SD (send data) on all of the time.  It should not be.  It's almost as if something else is controlling the modem.

Are you only using the serial ports on the MB?  Any special reason why you have them configured as COM2 and COM3, not COM1 and COM2?
Oh, according to everything I have seen the KG7 is supposed to have 2 serial ports.
HMCSAuthor Commented:
I had the modem on Com one and that is where it was when the problem started. I moved it to com 2 in an attempt to  fix the problem. I really should delete the burned out modem from 1.5 years ago from the port it is now on. I doubt this has anything to do with the problem - since it has existed on a port one way or another since it went poof on me.

Speaking of half duplex there is I think connected with the sound a half duplex sound device - does this have anything to do with the problem?

.Also I am only using the 2 mentioned serial ports. Nothing else is connected, unless I am terribly wrong.

I have the computer on now and I made sure the phone cable was unplugged and the SD light was still on - in fact it comes on almost as soon as the computer is powered on.

So does this mean technically that the serial port is not entirely dead as earlier suspected?

I am baffled !
As it seems that neither COM1 or COM2 are currently working, I would suggest that you:

Delete the definition for the "bad modem" from Windows, shutdown and physically remove it from the computer.
Restart the computer, but go into BIOS setup mode and in the BIOS setting you make sure that both are set using the default options for COM1 and COM2.

The re-boot the OS and see what happens.  I find it kind of hard, but not impossible, that both serial ports went bad at the same time.  Unless one has been bad for awhile and you just didn't know it.

The duplex on the "sound" was most likely as an interface for using you sound card in combination with your modem as a speaker phone.  Real expensive speaker phones can do full duplex (both ends of the conversation talking at the same time), whereas most cheap speaker phones and modem/sound card combination can only doe half duplex.
Oh, can you tell me exactly what brand and model modem you have?
HMCSAuthor Commented:
Looking in the BIOS I see the following:

Onboard Serial Port 1: 3F8/IRQ4

Onboard Serial Port 2: 2F8/IRQ3

Then I see this: Onboard IR function - Disable
IR Function Duplex - Half


I have not looked at the computer itself to see what the values are - I suppose I look in Device Manager for that  ?

I also have not looked to see if there is a 2nd serial port present in  the back of the computer.
HMCSAuthor Commented:
I also backed up the computer 2 weeks with system restore and without any luck :-(
HMCSAuthor Commented:
I got to playing around with the computer and at one point I rebooted it and then I got this message about "found new serial port" and then I got another message about something pertaining to a half duplex device. I immediately thought it was about the external modem but it didn't work.

I got to further playing around and decided to query the olfd internal modem and lo and behold it "answered". I found out that the phone cord was still plugged into the back of the computer and I traced it back, on hands and knees, to a point near the phone jack.

I tried dialing out and it said "There is no dial tone". I immediately remembered that I had my vista computer online using this phone line. I quickly disconnected and redialed and lo and behold it I a 24 kbs connection. I haven't redialed to see if I could get a better connection since it was downloading an update to my anti-virus.

Anyway I disconnected and redialed and it kept saying there was no dial tone. To this very minute
I've not gotten the internal modem to work again.

This does not solve anything and I'm still left with an external modem that once worked and now doesn't work. I even switched out the modems to see if that would make a difference but it's the same old thing over and over.

So looks like it's back to square one again - no working modem !!!

HMCSAuthor Commented:
The external modem is a Trendnet (agere) TFM560X
--> I have not looked at the computer itself to see what the values are - I suppose I look in Device Manager for that  ?

Yes, look under Ports (COM & LPT).  You should see at least 2, COM1 and COM2 which are the on board ports, and possible on more for the other modem (COM4).

You said that the modem was on COM2 but you changed it to COM3, how did you do this?

You may want to download the most recent drivers for TRENDnet modem on the computer that is NOT working.  You may also want to compare the driver levels between the two computers.  Although external modems like this one should be a real modem (as opposed to a soft modem) the "drivers" may actually update the code within the modem.

It sounds like you have two computers and one dial-up line.  What I would suggest is that you get a couple of cheap NIC's and connect the two computer's together using a LAN connection.  Then on the one computer that has the modem working set it up Internet Connection Sharing (ICS).  That way both computers can talk to each other and access the Internet at the same time.  

Now, dial-up shared between two computers will not be the fastest in the world, but it will work.

I still don't like the fact that the SD light goes high (turned on) and stays on.  It's almost as if there is something that is attempting to use the modem all of the time.

HMCSAuthor Commented:
I changed the com by removing the modem and reinstalling it. I have 2 phone lines and 3 working computers (counting the one with the modem problem).

I'll see if trendnet had drivers for the modem - I have used the ones within windows itself with no prior problems.

I'll download the drivers on my Vista computer and transfer them via USB stick.

I'll get to all of this tomorrow, as it is late and my arthritis is not exactly being peaceful tonight.
--> I changed the com by removing the modem ...

If you mean the external  modem, I'm still  confused.  Serial ports don't change their setting (IRQ number and IO address) based on removing  and reinstalling a modem and this (IRQ number and IO address) is what determines the COM port.  Now, internal modems and USB modems can have their com port setting changed by uninstalling and reinstalling.  But if you don't change the BIOS settings, COM2 and always going to be COM2.
HMCSAuthor Commented:
Well all I can tell you is that when I reinstall the modem I am given a choice of either com 1 or com 2, if the internal modem is present sometimes that changes.

I hope I can remove the internal modem - believe me it will be a task for me to due to the fact that it is at the bottom of the tower and it is in cramped quarters & I have little choice in the matter but I will try and also I'll look for that second serial port on the back of the tower. I have not been able to fully see the back of it but perhaps I can turn it enough

Hopefully I'll be able to work on this today. I have several things to do and will also be out of town this weekend. This has been a crazy week and the next looks to be no better.
HMCSAuthor Commented:
Sorry I have not been available - I am in the middle of taking care of some problems with my dad who is 92 years of age. I hope to be able to continue with this by the weekend, if not before.

Thank you for your patience !!!
No problem, you dad is way more important than this.
HMCSAuthor Commented:

I'm about ready to resume working on this modem problem. I should be on it tomorrow (07/04/08).

My situation here is at a point where I can just about resume normal activities.

I will be checking for an additional serial port connection and also removing the broken internal modem that was hit a year ago by an electrical surge which probably came from the phone line and not the power.

Nothing so far has hanged.
HMCSAuthor Commented:

I was about to get on my knees and with considerable effort turn the tower around when I decided to make one last ditch try at the modem.

I did a query of the modem and it actually answered !!! I then plugged in a connector into a phone jack and it actually worked.

I have NO idea what or why it worked. It has been working flawlessly ever since like nothing had ever happened before.

Now this leaves us in a sticky situation !!! You invested alot of time in getting into this problem and I feel like it is only fair that you receive the credit.

What I'd like you to do is write something up as a closing and list the various causes and solutions that were possibly available concerning this problem.

I realize that we may never know what caused this problem to happen in the first place and I feel it would be unfair of me not to award points for your efforts.
HMCSAuthor Commented:
The computer was barely turned on since 6/18/08 and became "fixed" on 7/4/08. You could be right on the P & P situation. It sounds like something that might have happened.

I hope this never happens again but at least I am confident that we have covered alot of ground in working with this situation.

I am going to look into the point situation and will let you know what I find out.

Thanks for the help and your time and helpfulness :-)
HMCSAuthor Commented:
I need to know if you have received points for this question - I requested that you be given the point - regardless of the actual outcome.

Please let me know as soon s possible
Yes, I did receive points.  Thanks.
HMCSAuthor Commented:
Good to know - thanks for your excellent help !

Be well and take care :-)
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