Applies To: SharePoint 2010, Visual Studio 2010

If you’re running Visual Studio on the same machine with SharePoint 2010 you are probably familar with this error message:

“An unhandled exception (‘System.Security.Cryptography.CryptographicException’) occurred in OWSTIMER.EXE [#]. The Just-In-Time debugger was launched without necessary security permissions. To debug this process, the Just-In-Time debugger must be run as an Administrator. Would you like to debug this process?”

In fact, you are probably very familiar with this dialog since it will pop up at least once a day. If you haven’t logged in in a while, then you will have multiple windows to cancel debugging in.

The problem is due to a threading issue related to an encryption key used by the OWSTIMER service. In SharePoint 2010 the timer service gets recycled daily (default is 6 AM) using a timer job mysteriously called “Timer Service Recycle”. The details aren’t all that important, but you can read more here and get even more information about how the mistake really occurs here. To summarize, the key isn’t found due to impersonation issues. (BTW, that number at the end of the error message is just the process ID and will change each time.)

Bottom line for me is that the error is not really a problem and can safely be ignored in your logs. The annoyance comes when you have Visual Studio installed and the JIT debugger is enabled.

You can either adjust your settings using the registry, or even better, just open up Visual Studio (2010) and adjust your options. Using the menu, choose Tools > Options. Then expand Debugging from the tree on the left (if it isn’t showing, check the Show all settings box) then choose Just-In-Time. To turn it off, just uncheck all the boxes and press OK:

Now those annoying messages will stop and the people will rejoice. Just remember that it can be very helpful to turn these back on when attempting to debug certain types of things (Custom Timer Jobs for instance), but be sure to bookmark this page because you will forget to turn it back off and then you will be sad again and I don’t want you to be sad.