Error when compiling using excel

Question

I access to the objects com of excel from aspx script, and I have added it into references. Normally it works perfectly, but at the time of executing there are it times that to me the error leaves that I beat down. But if I give to the menu "Build" -> "Rebuild solution", the application works perfectly and compiles without problems. Somebody knows because it can be? Thanksss Description: An error occurred during the compilation of a resource required to service this request. Please review the following specific error details and modify your source code appropriately. Compiler Error Message: CS0006: Metadata file 'c:\windows\microsoft.net\framework\v1.1.4322\temporary asp.net files\eptisa\5ce3ba4a\20f48b27\assembly\dl2\3f2655 9d\003e3bbf_0323c201\interop.excel.dll' could not be found Source Error: [No relevant source lines] http://hhdirecto.webcindario.com