We have code that checks for the presence of the VSTO 4.0 runtime and downloads it, if missing. This has worked fine until today. It seems the VSTO runtime file has gone missing from MS. Does anyone know anything about this? Can we tell our clients it's an MS problem and will be cleared up shortly? Google doesn't find any comments about the file being removed.
Thanks.
Note: the latest update to the VSTO Runtime (from November 2012) has merged the VSTO Runtime packages from two files (x86 and x64) to just one file. The download location has also moved. Follow this link for the latest version of the download page: http://go.microsoft.com/fwlink/?LinkId=140384 (referenced by MSDN documentation, such as http://msdn.microsoft.com/en-us/library/ms178739(v=vs.110).aspx).
If you're looking for a persistent link to the latest version of the runtime, you can use the same link that's referenced by the VSTOR Bootstrapper (used by ClickOnce installation). That link is http://go.microsoft.com/fwlink/?LinkId=158918.
Here is latest link: VSTO 2010 Runtime
EDIT: This is a 'permalink' and should always take you to latest and greatest
来源：https://stackoverflow.com/questions/7559616/vsto-4-0-runtime-download-missing-from-ms