Unanswered: Error 3043 In VB/Access App Since Migration To Win 2000 Server
I have a VB5 SP3 / Access '97 app that has been running smoothly for years. Recently, users have been getting an occasional "Error 3043" disk or network unavailable message. The error is not reproduceable on demand - it occurs randomly. Several changes were recenly made to our hardware but I can't figure out which one is causing the error.
1) Our old P-200 servers were replaced with 900 Mhz servers running Win 2000 SP3. The network runs slower with the new servers! Some of the original hubs and switches in our network are old and only run at 10Mps.
2) The Access database was not converted to the Access 2002 format so older PC's (with Win 97) can still use the software - So it still employs the original (seperate) .mdw security file. Maintenance is done from Office 97.
3) Older workstations are P-350's & P-500's running Win 95 & Office 97 while the old P-166's were replaced with Win XP Pro and Office 2002.
My guess is that the old 10Mps speed limitation on some of our network hardware is the bottlkneck. I know there's a lot of variables but at this point - any ideas on what's causing the error would be greatly appreciated.
I was fighting this error for more than half a year with no success - I've split the application on front end/back end, explicitly setting object variables to 'Nothing', checking the system environment TMP variables - everything was done according to MS's guidelines for this error, and according to advices from other Access users.
Finally, the solution that seems to have been solved the problem, was replacing the network interface cards on the machines that work with my application. Prior to this, they were equipped with old combo 10/100 NICs from unknown Taiwan/HongKong manufacturers. I replaced them with new 100 Mbps cards with genuine Intel chipset, and for the last 2 weeks the 3043 error did not appear at all!
The conclusion is, that Access is very sensitive to the smallest delays in network response, so you should consider replacing the NICs, hubs and cables in your network environment, and I think this will solve all of your problems, without changing anything in code.
(If possible, a full reinstall of Windows on the workstation machines would help a lot too)
Thanks for the time and detailed response. It is starting to look like a "traffic" problem. The users that are getting hit with the error message are supervisors who are running more processing intensive parts of the app. They retry these same tasks again ater and it will not only run successfully but also runs at the normal speed.
One of my biggest concerns is the older parts of the LAN hardware which are limited to the 10 Mps.
If a PC (these happen to be Dells) comes with an integrated NIC card, can you disable the original and install a second NIC card?
I got a response from another forum where they suggested doubling the "page filing system" settings. I'm assuming this a setting on the server. I am not a network expert and unfortunately, neither is our network administrator. Bad situation here.
I'm not quite sure what they mean about "page filing system", but in my case everything went fine just by replacing the old network cards.
The envoronment there is 4 Win98 clients, connecting to a Win XP Pro server, all running Access 97. There are other older machines on the network which have 10 mbps cards, and because of them, the entire network is set to run at 10 mbps, but this doesn't seem to be a problem anymore. After I replaced the NICs, I've tested the system by creating an infinitte loop requesting complex queries against the largest table in the database, at the same time copying a big directory over the network, and having Outlook download a big email attachment - everything passed for half an hour without a single error.
Try to monitor the network traffic on your server - if it is WinXP, press Ctrl-Alt-Del and then look at graph under the Network path - if it goes over 50-60%, then a faster network would be required. Also check if the hub's Overload (Conflict) LED is blinking too often.
About the Dells, I don't see a reason not to add another NIC - after you do that, you should disable the original built-in card either by the CMOS setup, if there is an option for that, or through the windows control panel.
Please, be aware, that after each occurence of the 3043 Disk/network error, the database should be compacted (and repaired if needed), because serious data integrity damages could happen. And make backups every day, until this problem is resolved.