How to make the latest workflow deployment take effects

Recently during the development of custom workflow activities, I got an annoying issue.

During the development, after deploying the latest version to SharePoint, I realized that normally the previous version is still in charge, so it will be impossible to debug the code. Resetting IIS and visual studio doesn't fix it unless reboot the whole SharePoint server.

Obviously some process is still holding the previous version.  There are not much possible processes which may cause this issue.  After some test, I found that "SharePoint 2010 Timer" is the one!

We can start up "services.msc" to restart this service manually, or run the script below:

net stop "SharePoint 2010 Timer"
net start "SharePoint 2010 Timer"

or

net stop SPTimerV4
net start SPTimerV4

If you got the exception "CryptographicException" during the service rebooting, please follow here to avoid it.

PS: this may also work on SharePoint 2007