This is a very intermittent behavior. I usually get this problem once or twice a month. The following steps will help solve the problem easily.
Try iisreset before trying anything else
Step 1: >> Open Run (Ctrl + R) >> type iisreset
If this does not work, try step 2.
Step 2: Open the task manager >> Processes >> select the Process and right-click >> complete the task . This should kill the IIS workflow.

If step 2 does not work for you, go to step 3.
Step 3: Task Manager >> Services and restart IISADMIN.
Some of you may not have the IISADMIN service, so if you see IISADMIN, right-click and restart.

Sangram Nandkhile Nov 26 '15 at 6:04 2015-11-26 06:04
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