Error 3043

We are supporting an older app written in VB 6.0 (sp5), with Jet 3.51
connected to Access 97 databases.

For most users, the system works great, but at a few sites we hit error 3043
which then causes the dreaded 3343 error. At one site, this seems to happen
on an almost daily basis.

We have been making changes, to keep the databases and tables in the closed
state more often, but the app is Accounting and in many cases this is not
practical, it also seems to slow things down.

I have waded through a variety of white papers, but we just can't seem to
solve the problem. The most common idea seems to indicate bad NIC/cables
or hub, but we seem to hit this error at other users perhaps every month or
so, so it still seems software related.

Any ideas, or do I just need to submit to Microsoft and make all my users
buy SQL server?

Thanks!

Dave.