在某些情况下，重新编译和重新构建并不能帮助克服这个问题。 另一个潜在的解决方案是从解决方案资源管理器中删除带断点的源文件，然后重新添加它(例如通过从文件夹中拖放)。

注意vs中的“Output”窗口，它会告诉你加载了哪些程序集以及何时加载。您可能会看到正在加载文件夹中某个位置的程序集的旧版本。

例如，如果您有多个程序集，并且当前正在尝试插入其中一个支持程序集，CLR将处理程序集解析，这可能会加载您在项目中引用的程序集文件以外的另一个程序集文件。

This happen often also if you are using a file references to binaries (instead of project references to code in your project), and the compiled binary that you are referencing falls out of sync with the corresponding source code on your machine. This can happen because you downloaded a new version of the binary from source control without the new source code that went with it, or you have a few versions of the binary on your machine and are referencing an old copy, etc. If this is indeed the problem, it's a good reason to use project references as much as it practical.

如果您在调试构建配置中未选中DLL项目，那么您的新代码将永远无法构建!

转到构建—>配置管理器…(在VS2010中)，并检查您正在尝试调试的代码的项目是否为当前构建配置进行了检查。

你做过这种事吗?

是否继续运行最后一个成功的构建?

如果您勾选了方框并按下“是”，即使您的项目没有编译，您也将成功运行最后一个构建。这意味着无论何时设置断点，都将得到该错误。

试着改变这个值:

工具 选项 项目和解决方案 构建并运行 在运行时，发生构建或部署错误时:不启动

I suffered from this recently, and in my case I traced the problem back to something I was doing when testing: changing the system time. I'm not suggesting this is the case for everyone, but thought I'd mention it since it hasn't been mentioned already. It appears if you start moving the clock around between debug builds then it can get very confused about what order various files have been created it - I can only assume it is using file modified dates to determine if the source code is valid or not, and which binaries it needs to recompile.

这也是一个重新保存网页的选项。配置以碰撞其修改时间。