Windows SBS 2008 network: Vista and 7 clients disconnect randomly from server

Posted on 2010-11-24
Last Modified: 2012-05-10
I have a customer with a LAN consisting of a Windows Small Business Server and 5 workstations:
Windows 7 Pro (1)
Windows Vista Pro (2)
Windows XP Pro (2)

There is a shared folder at the server, which is mapped as F: at the clients.
Their main application is an Access 2002 database with a Front End/Back End configuration.
I upgraded SBS from 2003 (32 bit) to a new server with SBS 2008 (64 bit).

After that , the clients with Windows XP have no problem. The other ones, get "disk or network error" randomly, while they are working with the Access application. This never happened with SBS 2003. They also get a similar message with a Quickbooks Client/Server configuration.

All Clients are connected to a single 16 port network switch which I just upgraded from 100 Kb to 1 Gb. It shows the problem with both switches.

I tried the Microsoft article but it didn't make a difference.

I suggested the server upgrade and I've spent 2 months looking for a fix and at this point I'm out of ideas. It's also embarrasing. This is a very good customer of mine.

Could you please help?

Thank you very much!

Question by:microlar
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 9
  • 4
  • 3
LVL 11

Expert Comment

by:Paul S
ID: 34207875
Disable TOE on the server:

Update the NIC driver to the latest on the server and the clients. IF the NIC driver is the latest already and it is the only NIC driver you have tried, then downgrade to a previous version. Make sure all the firewall rules are configured properly and make sure that the antivirus software is not causing a problem. For testing purposes you could uninstall the antivirus software for a few days and see if that helps.

Also if you don't use IPv6 you can disable it on the server and the clients. It may help. you can also run iperf between the clients and the server to make sure bandwidth is good and that there is not duplex mismtach, etc... (

I assume you have done all the microsoft updates on the client and servers already.

Author Comment

ID: 34208215
Computer Guru 777:

Thank you for your prompt reply.
This happens with the former and the latest NIC driver, which is different in all three computers.
I did uninstall the Internet protection software (Trend Micro Worry Free Business Security - I tried versions 6 and 7) and still happened, so I put it back.

Server and workstations have all latest updates from Microsoft and hardware providers.

Let's not forget that these workstations never had a problem with the same hardware, network and Internet Protection software before I upgraded the server.

The outstanding differences (as far as I can see) are:
Windows SBS 2008
64 bit server operating system
Windows Vista and 7 instead of XP

Thanks, again.
LVL 11

Expert Comment

by:Paul S
ID: 34208478
what about my other suggestions (TOE, iperf, ipv6)?
Salesforce Has Never Been Easier

Improve and reinforce salesforce training & adoption using WalkMe's digital adoption platform. Start saving on costly employee training by creating fast intuitive Walk-Thrus for Salesforce. Claim your Free Account Now


Author Comment

ID: 34209246
I just disabled TOE and IPv6.
Users are off for the rest of the week due to Thanksgiving.
I'll now if it worked by next Tuesday, November 30th.
LVL 77

Expert Comment

by:Rob Williams
ID: 34210428
It is not an answer to your problem but I thought I would 'chime in': Do not disable IPV6 on SBS 2008. This will cause numerous "known issues". There is absolutely no need from a performance or troubleshooting perspective.

Disabling TOE is a good idea in most cases but doubt it is related to this problem, it usually is more of a performance issue.

When the clients are disconnected from the SBS do they loose ALL connectivity or just Access and QB connectivity?
i.e. is the mapped drive shown as disconnected, can you access other shares, can you ping the server?

Author Comment

ID: 34210666
Thank you for the advise about IPv6. I had no idea about the "know issues".

The disconnection happens only within the applications. In Access much more often that QB, but Access database is being accessed by at least 3 users at the time, QB only one.
They can minimize the application screen and perfectly open the window for the mapped drive or connect to the Internet, etc.
It seems like it happens for a fraction of a second (enough for Access to show the error message and stop all operations) and then it gets restored.

At one point I thought that the disconnection at the Vista and 7 computers may have something to do with the addition of the XP users who arrive later to work. I had an Access screen open at a Vista computer and when the XP computer logged into Access the Vista showed the "disk or network" error immediately. It didn't happen consistently though, but so doesn't the disconnection (randomly 4-8 times a day).

I closely timed the occurrence of these disconnections, but I couldn't find anything at the event viewer, server or client.
LVL 77

Expert Comment

by:Rob Williams
ID: 34210685
Very odd. Can you post the specific error messages.

Author Comment

ID: 34213731
"Disk or network error" in Access at which point all boxes on the screen will show "Name?" and something like "Cannot file your company file" in QB.
LVL 77

Expert Comment

by:Rob Williams
ID: 34213815
Which versions of Access and Quickbooks? Quickbooks is or at least was an Access database I believe so that may explain why both apps

Just to confirm, none of this is over a VPN or slow link of some sort? I am assuming based on "All Clients are connected to a single 16 port network switch" this is all over a local LAN.

Author Comment

ID: 34232730
I didn't have a chance to get feedback from the users due to the Thanksgiving holidays.

Monday, November 29th, 2010, update:

I decided to remove Trend Micro from the server and the Windows 7 workstation.

I'll give it until Wednesday to see if the error pops up again.

I'll keep you posted.

Thank you all.
LVL 11

Expert Comment

by:Paul S
ID: 34271551
It is now past wednesday. Any updates?

Author Comment

ID: 34271581
Friday, December 3rd, 2010.

Unfortunately "disk or network error" showed up again after I removed Trend Micro.

I'm really out of ideas. I guess, my next move will be to reinstall Windows Server 2008 and I don't honestly have many hopes that's going to solve the problem.

I'll wait for further postings until Monday, December 6th, after which I'll close the case as unsolved.

Thank you for all your input.
LVL 11

Expert Comment

by:Paul S
ID: 34293922
a reinstall of the Server OS is never fun, but it will definitely narrow the scope of your troubleshooting whether it fixes the problem or not.

Author Comment

ID: 34397450

I finally got SBS 2008 re-installed and that apparently solved the problem.

This is the Premium version of SBS 2008 which comes with SQL 2005 and 2008.

I don't know how I managed to install SQL 2008 at the SBS server the first time but I couldn't do it again.

Windows Server monitoring and scan mail databases are not compatible with SQL 2008.

Also, the NTFRS wasn't working and I didn't try to rebulid it.

I don't know if the issues above may be related to my original questions or not.

Hopefully the problem won't repeat, and if it does I can work on a fresh start.

Thank you all for your suggestions.

Accepted Solution

microlar earned 0 total points
ID: 34715672

There is a known problem when you have a SBS 2008 with mixed clients connected (XP and Vista/ 7).

SMB 2.0 came out with Windows Server 2008, Vista and 7. XP uses SMB 1.1 (slower).

SBS 2008 should be switching automatically between SMB versions according to the client’s operating system with no problem… in an ideal world.

This switching, somehow, causes random disconnections in the Vista and 7 clients (my problem).

Solution: Disable SMB 2.0 for as long as you have co-existing XP and Vista/7 clients (

Once again, thank you for all your input.

Author Closing Comment

ID: 34759246
The problem has been resolved.

Featured Post

Microsoft Certification Exam 74-409

Veeam® is happy to provide the Microsoft community with a study guide prepared by MVP and MCT, Orin Thomas. This guide will take you through each of the exam objectives, helping you to prepare for and pass the examination.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Node.js 11 82
Windows 10 64bit Mapped drive issue 38 124
hp Printer driver does not install something is blocking it not sure what 4 59
PCAP file format 4 36
When it comes to security, there are always trade-offs between security and convenience/ease of administration. This article examines some of the main pros and cons of using key authentication vs password authentication for hosting an SFTP server.
Most of the applications these days are on Cloud. Cloud is ubiquitous with many service providers in the market. Since it has many benefits such as cost reduction, software updates, remote access, disaster recovery and much more.
After creating this article (, I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
This video gives you a great overview about bandwidth monitoring with SNMP and WMI with our network monitoring solution PRTG Network Monitor ( If you're looking for how to monitor bandwidth using netflow or packet s…

752 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question