Hi
There are some things you can check which may help to minimise your problem.
Firstly, make sure that the DNS is setup correctly. Check the machine that hosts your share has DNS properly setup - you can check the DNS event logs and then follow up any errors you find. Do the same for your machine - examine the event logs and follow up any DNS related errors or warnings.
If you do find any errors in your DNS logs (or any other logs for that matter), go to Microsoft's web site and use their search page to check the event. If you have no joy, try www.eventid.net - this is a very good site and has real-world solutions to common problems.
Also check your machine is able to log onto the network as well (not only do you have an account, your computer has one as well).
I have seen this 'no logon server available...' error quite a few times - especially after the domain network at our company was first setup, and these errors have been almost eradicated by ensuring the DNS is running smoothly. Commonly, the solution was to uninstall DNS from the domain controller, then reinstall - after doing this 3 times the DNS has been humming along very nicely.
This may not solve your problem but it is a good starting point for troubleshooting.
Good luck
