Processes w3wp.exe are not Being spawned (finalized)

Hi.

I configured the IIS DefaultAppPool to run with just one process (Maximum Worker Processes = 1). I also configured the DefaultAppPool  to recycling periodically.

After some time in Windows Task Manager there are two w3wp.exe process associeted to DefaultAppPool. When I call the pool recycling only one process is killed. At this time the pool/site is workin fine. If I execute IISReset the "orphan" process keeping running and the DefaultAppPool doesn't work anymore. The IISReset is executed without error.

Then to make the pool/site works again is necessary kill the orphan process by Windows Task Manager.

This is the environment:

OS: Windows 2012 R2 Standard. Version 6.3.9600 Build 9600

IIS Version: 8.5.9600.16384

I thank you, if anyone can help.