random network disconnections

[HipHoper]

Hi all,

For the past few months I'm experiencing reoccurring problem at one of my client's site.
there is one station (dual core/2gb/128gb ssd/win 7 x32)that works on an sql database that is located on the office file server (sempron 3400/2gb/xp pro).
All of the office computers (about 12 computers and 4 network printers) are connected to a 24 ports hub and dlink 2670U adsl router.
every few days there is a disconnection on the workstation i mentioned.
I tried :
1. reinstalling windows on the WS (few months ago - because of a virus)
2. added a NON ON BOARD network card (like a year ago)
3. replaced the network cable that goes to the router
4. Added a router for internal network to seperate it from ADSL router (just few days ago)

When I replaced the network cable that goes to the router, The computer worked stable for few days, But few days ago disconnections returned.
I installed ping monitor software over the weekend (After adding a router), And result were good (maybe 20 pings dropped out of 200000 pings, But this morning it disconnected again from the network (There was no ping to router AND to ADSL router at the same time).
I suspect it might be the network card, Or something to do with the SQL database (The computer OR the server keeps working after the disconnection and the server still has internet).I have this intel pro network card I kept for some time and i considered to put it in the specific WS.
What would you suggest ?
Thank you

[Steve R Jones]

Does the disconnect happpen while the pc is in use or while it sits idle and the network adaptor goes into sleep mode?

For grins, click on Start -> Run and type CLICONFG and make sure TCP/IP and NamedPipes are enabled.

[HipHoper]

Hi Steve

It happens while the accountant works on the computer.
What the enabling of the NamedPiped and TCP is suppose to do ?

Thank you

[HipHoper]

I'm sorry i misled you, The server is running Borland socket server and NOT SQL.

[slgrieb]

One possibility is that there may be an IP address conflict in the network. Windows doesn't always report those correctly, and they can come from unexpected causes. One of my credit unions recently had a power outrage, and afterwards started to experience erratic internet connections. They also use Shoretel's VOIP phone system, and one of the phones was also working erratically even though the phone system is on a separate T1 line. Turned out that somehow after power was restored, the IP address on the screwy phone had been reset to the same address as the gateway. Correcting the phone's IP address fixed the connectivity problems.

[HipHoper]

Hi Slg,

Hmmmm all of the computers in this network are getting their IP's from the router DHCP pools (Except for the 4 printers that I gave manual IP's).
It happend with the older ADSL router (Which also worked in DHCP), And with the new one too, So I suspect thats not the case, But I might be wrong.
Anyway I changed the network card to intel 100 pro card and will follow the behavior of the net for the next few days. The person that is working on the WS is leaving for few weeks vacation soon, So it might tak some time to get stability results.
I talked today to the accountant software support, And they offered maybe to install the WS on the server itself and then install RDP so she can access the WS/Server from her computer on the office net.

Thank you for your insights

[slgrieb]

I just threw out the suggestion as a long shot, 'cause you sometimes find answers in unexpected places. With a single machine experiencing the problem, and no obvious solutions, it was worth a look. I'm sorry, but I just can't see an obvious hardware issue; and that includes power saving settings for the adapter and the like. So, that doesn't leave much except malware or a Windows installation that's so messed up that you need a drive wipe and reload. After all, you've experienced the same problem with two network adapters, so I can't see how hardware is a factor. My experience is that power saver settings for network adapters are very, very seldom the root cause for connection issues. Doing a repair installation of Windows can leave a multitude of problems unresolved.