Stephen,
Today again, it's back to classic mode. I didn't do anything. This is very frustrating. Does it change whenever I change code in web.conifg? Please sort out this issue on a priority basis as I have wasted lot of time on this. I want httperrors control in web.config in Integrated mode and I want it to stay that way. I will watch my test web site (given in the above ticket) for a few days before changing over other web sites to the new scheme.
BTW, I could do this on another company's shared Windows web hosting without any problems. The difference is that they have a Plesk control panel and that seems to be better at controlling httperrors and much more flexible where I need minimum support. Any chance of you going the Plesk way? May be you will reduce your support efforts too.
Thanks,
Sanjay