LP on .NET

April 15, 2010

SQL Server 2008 Management Studio Express Installation Problems

Filed under: .NET,Microsoft,Software Development,SQL Server — Larry Parker @ 8:50 pm

Boy was this a day to remember.  Granted it was April 15th, but it had nothing to do with taxes.

I needed to apply a short SQL script to a database, so I fired up SQL Server 2005 Management Studio and tried to connect to my local SQL Server 2005 Express instance.  But surprisingly, I got this error:


[This version of Microsoft SQL Server Management Studio can only be used to connect to SQL Server 2000 and SQL Server 2005 servers]

It turns out that my local SQL Server instance was no longer SQL Server 2005 Express but was instead SQL Server 2008 Express.  I recently installed Visual Studio 2010 on my development machine and it must have upgraded this.  Fair enough.

So I proceeded to run SQL Server 2008 Management Studio Express instead so it could talk to my SQL Server 2008 Express instance.  The only problem was that it wasn’t under the Microsoft SQL Server 2008 program group.  I guess VS 2010 did not install this but instead just installed the SQL engine itself.  I cannot understand why Microsoft would not include the GUI tool for SQL 2008, but surely they have a good reason.

So I found the SQL Server 2008 Management Studio Express link and proceeded to install that.

When I got to the Installation Type screen, I selected “Add features to an existing instance of SQL Server 2008”.


This seemed like the logical choice since SQL 2008 was already installed by the Visual Studio 2010 install.

But logic did not prevail in this case.  When I got to the Feature Selection screen, there were no features to select:


After searching around on some blogs and forums, it turns out that I should have selected “Perform a new installation of SQL Server 2008”:


Not very intuitive, but at least now I could select the Management Tools feature:


After successfully clicking through the next couple of wizard screens , I ran into another snag – this time on the Installation Rules screen:


When I clicked on the Failed hyperlink next to the “Previous releases of Microsoft Visual Studio 2008” entry, I got the following error:


[A previous release of Microsoft Visual Studio 2008 is installed on this computer.  Upgrade Microsoft Visual Studio 2008 to the SP1 before installing SQL Server 2008]

So I brought up Visual Studio 2008 to check if I had SP1 installed, and it turned out that I did.  Huh??  At this point, I felt like I was on Candid Camera (ok, I’m showing my age – I should have said Punk’d) and probably uttered a few expletives.

After looking around for Allen Funt, I mean Ashton Kutcher, I tried repairing Visual Studio 2008 by going to Control Panel and bringing up this screen:


Then I uninstalled SQL 2008 Express and reinstalled it again, but got the same problem on the Installation Rules screen where it was saying I needed VS 2008 SP1.

Note: make sure you install SQL Server 2008 Express with Tools!  At first I just installed SQL Server 2008 Express and had to waste more time figuring out why Management Tools was not available on the Feature Selection screen.

Back to the VS 2008 SP1 problem…  After checking around on a few blogs and forums, the general consensus was to uninstall Visual Studio 2008 SP1 and reinstall it.

Instead of suffering through completely uninstalling and reinstalling Visual Studio,  I tried out a shortcut and just reinstalled the service pack from this link.  I didn’t encounter any problems with this, but I highly recommend that you back up your Visual Studio 2008 settings first (under Tools | Import and Export Settings…).

So then I went back to the SQL Server 2008 Express with Tools installation and this time the Installation Rules passed the check.  Progress at last!  🙂


From there it was just a matter of clicking through the remaining wizard screens (and setting up some security) and it finally went through!


Wow.  That was a full day of work.  I finally got to run my SQL script at the end of the day, which took all of 30 seconds to complete.  Gotta roll with the punches, I guess.

Anyway, I sincerely hope this helps others out who have run into this same nonsense.  If you would like some more information on this problem, you can read more here and here.


April 8, 2010

Deferred Procedure Calls and CPU Usage

Filed under: Software,Windows — Larry Parker @ 11:13 pm

I recently started using an old Dell Dimension desktop (circa 2005) on a regular basis and for the past couple of months have noticed that the CPU would periodically increase to around 20% for no apparent reason.  This had been causing mouse slowdowns (giving it a rubber band effect as it moved across the screen) as well as audio pops and clicks as I listened to music.

At first I thought it was some service performing housekeeping and I just dealt with it.  The “CPU storm” would typically last for ten minutes or so and then calm back down.

But this week I just couldn’t take it anymore and decided to get to the bottom of it.  After some Google searches and various troubleshooting (see below) I encountered a common recommendation:  update the video drivers.

It turns out that my old NVIDIA geForce 6800 was running a very old driver, and updating it to the latest version fixed the problem!!  Beautiful!  🙂

Technical Details

What I found strange while troubleshooting was that Task Manager showed the CPU at 20% but did not indicate any process taking up much CPU time on the Processes tab.

After digging around a bit more, I came across something called deferred procedure calls.  According to Wikipedia’s entry on this, a deferred procedure call is a Windows operating system mechanism that allows high-priority tasks to defer lower-priority tasks for execution at a later time.

By a stroke of luck, I recently installed Microsoft’s Process Explorer utility to find out which process had grabbed hold of a particular file, and just happened to see an entry for DPC’s:


When the CPU storm was in progress, I indeed confirmed that the DPC’s were taking up a fair amount of CPU time, and this coincided with the slow mouse and audio pops.

Since updating my video drivers, I have not seen the DPC’s jump up very high for more than a second or two.  And my mouse and audio have been behaving great.

The storm has subsided and it’s been smooth sailing ever since!!

Hope this helps.

April 5, 2010

File Timestamp Problem under Windows Embedded

Filed under: .NET,C#,Windows — Larry Parker @ 9:35 pm

I ran into quite the interesting problem today.  The QA team was testing a module of mine that syncs up files via a WCF service.  The lab had a server and two workstations.  Things were working great on one of the workstations, but the other would not sync up some files.  Every time the workstation sent its file snapshot to the server it identified files that were out of sync and dispatched a sync package that then got applied at the workstation.  This cycle kept up throughout the morning.

After much debugging and viewing of various WCF trace files (using Microsoft’s invaluable  Service Trace Viewer tool), it turned out that some of the files getting synched up at the workstation were being touched (using .NET’s File class and the SetLastWriteTimeUtc method) with a timestamp that was a second ahead of what should have been written.

For example, if I set the file’s last write time to 8:50:37 AM, the file would then show 8:50:38 AM when I looked at its properties in Windows Explorer (the Modified field).  But some other files did get the exact timestamp I wrote out.  And, everything worked fine on the other workstation.

What gives??

It dawned on me that the difference between the two workstations was the operating system.  The machine running Windows XP worked fine.  The machine having the problems was running Windows Embedded POSReady 2009.  Hmmm…

I then wrote a simple program to reproduce and isolate the problem.  Here’s the code:

static void Main(string[] args)
    DateTime ts = DateTime.Parse("2010-04-05T12:50:00");
    for (int i = 0; i <= 59; i++)
        Console.Write("Testing {0}: ", ts.ToLongTimeString());
        ts = ts.AddSeconds(1);

    Console.WriteLine("\nPress Enter to exit...");

private static void TestTimestamp(DateTime ts)
    String file = "TimestampTest.txt";
    using (File.Create(file)) ;
    File.SetLastWriteTimeUtc(file, ts);
    DateTime ts2 = File.GetLastWriteTimeUtc(file);

    if (ts.Second != ts2.Second)
        Console.Write("Error!  Expected seconds={0}, actual seconds={1}",
            ts.Second, ts2.Second);


Here’s how it ran on the Windows XP machine:


And here’s how it ran on the Windows Embedded machine:


Strange — timestamps with even seconds work, but those with odd seconds don’t!  They get “rounded” up to the next even second.

My workaround was easy enough.  Instead of comparing file timestamps down to the second, I added some tolerance for a couple of seconds.  Works for me (and for QA as well).

But I’m curious as to what’s going on under the covers with the SetLastWriteTimeUtc on Windows Embedded (all machines were running .NET 3.5 SP1).

I’ll have to post this on the Microsoft forum and will update this blog post if I find anything out.  If any readers have encountered this problem, please let me know!

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