Strange development machine behavior Anyone seen this before?

My development environment has been having some bizarre behavior as of late and I wonder if any other niners out there have seen something like this...

Specifically most of the projects I work with are Silverlight applications hosted in IIS. My development environment attempts to mimic the deploy environment in that I also use IIS on my system rather than as ASP development server default. My development environment is a fully patched Win7 ultimate 64 bit system running a fully patched VS 2010 Ultimate as well. The silverlight apps I work on are typically hosted behind a forms authentication scheme so when I launch the application in debug it will first present me with my forms auth screen and I login then the silverlight app will stream in and run.

All is good at this point. Recently however three really weird things have started happening to this arrangement. 

First I login as stated above and then rather that the silverlight application coming up the browser will just hang eventually giving me what amounts to a 404 error. I can close the browser and return to the dev environment. If I debug again I usually will get past the login screen into the application proper but sometimes I might have to do this multiple times. This BTW never happens if I just open the browser and navigate to the local IIS site manually. I have tested that 100's of times.

Second and more annoying is that occasionally When I close the browser to return to VS, the VS wont come out of debug mode. It just sits there like its tracing my codes locked up tight and unresponsive. If I let it sit for oh 5 minutes or so I get a message that quickly pops up saying that VS is debugging, it then goes away and VS is back to normal. Couple this odd behavior with the point above and you can see that things are getting annoying.

Third and this one is most annoying I cannot breakpoint and step in my web service side of things. If I set a breakpoint on any of my webservices (WCF endpoints). It will stop there and I have maybe 30 seconds to look at stuff before VS will throw an error on the reference.CS file on the silverlight side of things with some error about the endpoint missing or something like that. I can break and step in the silverlight side of things all day no problems....

Any ideas as to what the hell is happening here. Or do I have to just PAVE the machine again and spend weeks getting all the tweaks and stuff back where I need it..

I have also noticed some strange lockup behavior with VS 2010 Ultimate SP1 on Windows 7 x64. In my case I'm debugging mixed managed/unmanaged code although I think whatever is causing it for me could be the same cause in your case.

Sometimes the debugger would hang when stepping from managed code into native code. Sometimes it would just completely step over the unmanaged calls instead of stepping into them. In those cases I need to put a breakpoint inside the unmanaged code to get in there. Yet other times all will be well and the next time I single step VS will either crash or hang, or throw bizarre unrelated exceptions out of the blue.

This issue is especially annoying to me since I just built quite a complex C# application that is supposed to be used to debug one of our unmanaged APIs, and then when I start using it I find out VS is flaky when debugging mixed mode code.

The hanging issue is a well known problem with VS (see here, and here) and was supposedly fixed in SP1, but if you ask me, it made it worse.

Other strange behavior includes the combo boxes in the toolbar sometimes getting some invalid width values such that it pushes other items off the screen. I then have to either reload the VS settings from ones I saved previously, or reset each combo box's width to something sane. This just tells me that VS has a tendency to corrupt its own internal data and who knows what else gets into a bad state.

Here are some of things that worked for me in the past:

• Since you are using Ultimate, turn off IntelliTrace in Tools > Options > Intellitrace > uncheck Enable IntelliTrace
• Close VS and delete the *.suo file. It seems this file gets corrupted sometimes. It stores your current breakpoints, open files, bookmarks etc so you will lose all those
• Export all of your current settings by going to Tools >Import and Export Settings. Then go to import/export settings again and this time select "Reset all Settings". Test debugging again and if it all works fine, go to import/export again and then choose to only import the most important settings (like fonts/colors, keybindings, window layout etc). Once you have a "working" configuration, export those settings as a "good" configuration and then always just import that one whenever things start getting weird again.

Good luck...

Hmmmm... I thought I had turned off Intellitrace already but I checked and it was on. I will run some tests now and see what I can come up with...Thanks

Gone back to a stock VS2010 setup. No Luck...

Removed the .SUO files from the projects I am working on.. No Luck

Intellitrace is off... No Luck

I am now working on building a bare bones Win7 VM with just enough stuff to support my projects, IE IIS,SQL DEV, Silverlight 4, some third party Silverlight components, (ComponentOne, Telerik, NorthWoods GoXAM and some others that we have made)

Will see if I can make a stable env out of that. I just hate the notion of development in a VM on a dev machine when the actual iron is running the same stuff and SO much faster....

One thing I have found in regards to the VS hanging after the browser is closed is that if I am not actually debugging on the ASP.NET side of things. (IE ASP debugging is turned off and only Silverlight debugging is enabled). The hanging of VS for 2-3 minutes goes away. Presumably because IIS and VS are not really talking to one another in that instance...

The Occasional Forms Login and silverlight never starts up leaving the browser with what is effectively a 404 error remains

The breakpoints on the webservice side will never get hit because ASP debugging is disabled so If you need to look at something happening over on that side of things I have to find another way to do so...