I am having similar issues.
All I have done is add another Web form called "TestForm.aspx"
When I recompile my code and run the application I get the parse error. All of the other pages work fine.
Server Error in '/Rjrt.QuipSap.WebUi' Application.
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Parser Error
Description: An error occurred during the parsing of a resource required to service this request. Please review the following specific parse error details and modify your source file appropriately.
Parser Error Message: Could not load type 'Rjrt.QuipSap.WebUi.TestForm'.
Source Error:
Line 1: <%@ Page Language="vb" AutoEventWireup="false" Codebehind="TestForm.aspx.vb" Inherits="Rjrt.QuipSap.WebUi.TestForm"%>
Line 2: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
Line 3: <HTML>