What is the best way to go about moving from VC 6.0 to VC 2005

I have been trying to port MFC application with arnd 10k lines of code from VC 6.0 to VC 2005.

When for the first time I compiled the code, I got arnd 200 compiler errors and 150 warnings.

I invested many hours to  remove all the errors and warnings.

I ran my application and it crashed. A reason I could found from one of the forums was change in implementation of one of the methods.

Now that I have a huge code base and there has been lot of changes from  VC 6.0 to VC 2005 and I can't test and correct the code all the time and make my stable/ legacy application highly unstable.

What is the best way to go about moving from VC 6.0 to VC 2005.

Can I get any support from Microsoft on this.

Also, can anyone also ellaborate on complier switches.
From last release, we have shifted our developement to VS2005. The problems which we faced were easily got fixed.

 I guess this will be of little help.

As you said that your Project get crashed this mean you are able to run the project .In this senario the easy and i think most sutable way is that you have to perform exception handling inside your code.

And Second when ever you make a huge project just Create a logFile inside your code to trap out all the error occured in your application so that if this gets crashed at client side or somewhere else you simply can ask for log file and can check for particular function instead of checking the whole sole code.