JBrennan
Trust me here, you are going to have to get a grip on what oplocks(opportunistic file locking) does.
Microsoft created as far as i know and included it in windows NT. Basically to speed up sharing of files in a terrible way that does not work with general programming of sharing and locking files or locking records within files.
Do a google on either "oplock" or "opportunistic file locking".
I believe linux has had to deal oplocks because of windows nt os.
Here is microsoft suggested way of controlling it with the registry.
http://support.microsoft.com/kb/296264I have read that microsoft did not want make any corrections to oplocks in order to sell MS SQL, that is their answer some i had read, but that does not solve my issue either.
You have to turn oplocks off all the workstations not just one if you are going to control oplocks from client computers.
Windows client workstations have a choice of either oplocks being off or on, the default on a windows workstation is it that is turned off(the windows registry entry for oplocks is not created.)
In Sme Linux, you can turn if off(on the server side) i believe, but you can leave it turned on, the default state, or set certain files names to not use oplocks. This is something that cannot be done in windows as far as i know.
By turning it off on all client workstations, this gives you a chance to test your software for trouble as well as performance.
As mentioned also, you can test or run access on another windows nt peer computer acting as a sole server, I did this for years before using Sme Linux.
There is also a setting on a windows nt os computer where you can set the oplocks to not be allowed in a server role, set the above microsoft website link.
If you set the windows nt os computer server to not use oplocks in a server role, you then do not have to make changes to any client computers registry as far as oplocks go.
and if you like that setup, as was suggested, run the computer without monitor and use ultravnc remote control software.
One thing to consider, was your access application written correctly to begin with for a multi-user system, if not, and it was written for a single user, then you will always have issues when it comes to multi-users.
One a sme linux server, i suggest doing what i did, have a way to see what files are in a open state, this will help you to possibly figure out what is going on.
See what files are open when a client computer has oplocks turned on compared to turned off.
Here is a problem i solved. We have databases in use with a certain program. Everything runs fine when oplocks are turn off, but there are some reports at the end of the day and end of the month where it would take 20 minutes to run these routines. To solve that problem, i only let a single certain workstation run these routines with oplocks turned on and all other workstations oplocks turn off.
Also on the Sme Linux server, i set vetoplocks for all files that had nothing to do with high performance in doing the daily and monthy routines, i tweaked my oplocks so to say, but like i said, on other client workstations the oplocks where all set to off using the registry entry.
And personally, i disliked Access from the first time i used it from years ago.
It will get you by for a few years, but then there is a time when you probably are going to have to bite the bullet and use something more robust and dependable.
If somebody tells me they written something with Access and are using that a database, i just think how low skilled they are with database programming.
I personally would suggest you move away from Access ASAP, even if it takes a few years to do it. And Dbase is not much different.
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