Problems Debbuging ASP.NET Ajax Application Through Localhost

I have developed a couple of ASP.NET application that use an HTTP Handler and an XSLT transform to populates a span element with a table displaying the results from a database query. When I try to debug these using localhost the results are no开发者_高级运维t always returned, some are returned but not all, sometimes there is html at the top of the span or it returns the error 12031.

I've read some posts on other forums that suggest that the 12031 error could be coursed when the viewstate too large. However I have tried disabling this and it does not seem to have any effect.

Also on the first application I developed I did not get this problem when I promoted it to the user test environment. I have not promoted the second application yet. However I am wondering if it could be a local setting that is causing this problem?

I would be most grateful if anyone has any ideas of what could be causing this problem as it is making it difficult to ensure it is working correctly and debug any problems.

Kind regards,

Caroline

Have you used Fiddler to debug the HTTP Traffic?