I am developing a web site that in which three pages use Web.config. I am having problems with these three pages. I have loaded on to the web page several pages that DO NOT USE WEB.CONFIG. On these pages I get errors when trying to access them from the web. I deleted ALL web.config files and the App_Data folder and reloaded my files with the same result. You can see the errors by going to MervNorton.com and clicking on my picture to get to the site under development.  Go to Members Only/Leadership/Vietnam Team, Members Only/Leadership/Board of Directors, Members Only/History/ 1^st Signal Brigade and Members Only/History/Signal Corps. All give the same error message which I do not understand. I have not had this problem when uploading other pages during the past several weeks.

What is the problem and what is the solution?

I think you've to set the customErrors mode of "Off". You'd b able to know what error shows up.