Craig Box's journeys, stories and notes...

Posts Tagged ‘dotnet’

ACT presents "Object reference: Not set to an instance of an object." when connecting via Citrix

Wednesday, May 23rd, 2007

The ACT! contact management application is a pig. There, I've said it. It's one of those programs that keeps changing owners - that's how much of a pig it is. Seems no-one really wants it.

They re-wrote it in .NET a couple of versions ago, and it ought to be better, but it isn't. ACT! throws "Object reference: Not set to an instance of an object." (a reasonably common .NET error) whenever it feels like it.

In my particular case, I could open it fine when using a Citrix desktop session, but as a published application, it would die all the time.

I tracked the problem to the seamless window. When you run seamlessly, you get Citrix's WFSHELL.EXE running, and not EXPLORER.EXE. You can force a published application to run at a certain screen size, which runs as if you were in a desktop. Hopefully the ACT! forums will give me a better answer.

Debugging .NET - "Common Language Runtime Debugging Services Application has generated an exception that could not be handled"

Friday, May 11th, 2007

ProfileTool doesn't work on half the machines I try it on. I get an error like:

Profiletool.exe Common Language Runtime Debugging Services
Application has generated an exception that could not be handled.
Process ID=0x14 (1300), Thread Id=0xe8(232)

Click OK to terminate the application.
Click CANCEL to debug the application.

There's no point searching Google for the process ID and thread number; they're unique to your instance.

What can you do here? You get an error suggesting that 'debugging failed' if you hit Cancel - this is correct, because you don't have a debugger installed!

First step, if you're running your .NET application off the network, stop, move it to your local disk, and try again. The default security policy doesn't let you do this - you can edit it in the Administrative Tools if you need to.

Now, if you still get the error, drop to a command line, and run the following:

ProfileTool 2>error.log

This redirects the standard error output to error.log, which you can then read. Linux/UNIX outputs this to the terminal by default; Windows hides it.

Thanks to Frank Racis, by way of Mohamed Yehia.

The actual error, in this case, was "No mapping between user accounts and security IDs was done", which really means "don't catch System.SystemException when you are throwing System.Exception". And when you're testing new builds, don't sit behind an ISA server which aggressively caches the old build.

ProfileTool beta released

Wednesday, April 25th, 2007

ProfileTool screenshotI don't often write code, but I do find it's a good complement to cricket watching. So, in honour of New Zealand playing Sri Lanka in the World Cup semi-final, I'm proud to announce the release of the first public beta of the IT Partners ProfileTool.

ProfileTool lets you take a Windows 2000 or XP user's profile and assign it to a different user, without having to copy any files or perform any manual procedures.

This is a common task for people who are taking a network of PCs that have not been on a domain, and joining them to one; or if you replace a domain controller without keeping security information, which is sometimes done on sites upgrading from a badly installed SBS 2000 installation to a nicely installed SBS 2003 installation.

It also has useful features for deleting a profile off the disk/from the registry, and changing profiles from roaming to local, replicating the features of the User Profiles capplet.

The source is available under the Mozilla Public License, with the implication of "Do what you like with this code, but if you improve it, I'd like your source to come back to me please".

T9 dictionary editor for a Smartphone

Thursday, April 19th, 2007

I have problems with my T9 on my Smartphone. For example, it seems to like the word "diem1t" rather than "didn't". Someone must have written a dictionary editor, right?

  • Pocket PC dictionary editor - runs on the device, but doesn't want to run on my iMate SP5 (crashes with an exception).
  • T9 Editor - doesn't like the T9AW.UDB my phone has (crashes with an exception).
  • msT9ed - also doesn't support the new format, but loads it with some weird looking data.

In other news, shareware authors could do to handle exceptions better.

Any suggestions?

Targeting .NET 1.1 harder than it seems

Wednesday, March 21st, 2007

I'd like my application to be able to run on .NET 1.1, so I've avoided using all the new niceties of .NET 2.0.

Or so I thought.

First, I experimented with MSBee, which lets you build for the .NET 1.1 environment using the VS 2005 tools. After seeing how many errors my code generated in 1.1, while it compiled cleanly in 2.0, I thought "maybe reimplementing this in VS 2003 might be easier".
And while I've specifically avoided some of the .NET 2.0 things that would have been really handy, like the SecurityIdentifier class, which makes handling SID-account mapping easy, there's things I didn't know would be a problem. You can't set a registry key to be a certain type in 1.1. And you can't use half the features that the designer implements for you automatically. And even if you could, you'd have to hack at it, because they separate code and design with partial classes in 2.0.

So, to summarize, looks like .NET was pretty crap prior to 2005. And that means you need to have XP SP2, because it's not supported on SP1.


RegUnloadKey failing with error 5 (Access denied)

Sunday, March 18th, 2007

Trying to unload a registry hive and finding access is denied?

I was loading in a user hive (NTUSER.DAT in the profile), and then opening the key using RegOpenKey (exposed as Registry.Users.OpenSubKey in .NET) to prove it was successful. However, I'd forgot to close this key, so the handle was staying open and thus you couldn't unload the hive.

Oddly, after some time, the handle would clean itself up, so it seemed more like a time or permissions based issue. Simple fix however.

A working release of ProfileTool isn't far away..

Left out in the .NET cold

Tuesday, July 18th, 2006

Hey, if Juha's blog is a NZ .NET blog, then dammit, I ought to be one too. Vote for me! I have a Smartphone, and wrote a program in C# once!

On that note, did you hear I wrote a program in C# once? Mostly while watching one-day cricket last summer, in fact. It progressed really well, and seemed like it would fill a need - it does profile management for Windows 2000/XP machines. I learnt a lot on the go, and got it to the point where I didn't think that I would be able to go much further without peer review.

So, I released it, and posted about it to some newsgroups. And got no feedback. Not one. Not a sausage.

Since then, I've actually gone to run it once, and found that it didn't actually work on .NET 1.1 - even though I'd deliberately eschewed nice new 2.0-only classes and done things The Hard Way for maximum compatibility, because I'd used Visual Studio Express 2005, it used 2.0 by default. I found out how to fix that, but by that time, it was quicker to fix the profiles manually.

I don't really enjoy programming the way that my programmer friends do. If I had a Windows programmer buddy to help me with the details and motivate me, then the Windows sysadmins of this world could end up with a pretty cool tool. So, 1. I think this post must make my blog the best .NET blog in NZ (cough cough) and 2. if anyone out there wants to help out with a useful C# project for Windows sysadmins, please comment below.

GNOME Remote Desktop Client

Tuesday, May 16th, 2006

Found through reading the dapper-changes list (thanks Matt): Gnome-RDP, a graphical front end for RDP (rdesktop), VNC (tightvnc) and SSH (via gnome-terminal). Written in .NET with GTK#. Looks good, will install it later and have a play.