Fixing The process cannot access the file because it is being used by another process. (Exception from HRESULT: 0x80070020)

I had some “Weird” things happening with IIS on one of my developer machines. After trouble shooting for a while I decided that was definitely not winning and removed all features from my pc that were even the slightest related to IIS, my pc required a restart so I did. When it came back I re-enabled all the features as I would normally do and then attempted to put my dev site in IIS. For some reason all the sites were stopped and when trying to start them I received the message

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Internet Information Services (IIS) Manager
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The process cannot access the file because it is being used by another process. (Exception from HRESULT: 0x80070020)
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OK
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This was very weird as I was at this stage thinking that there shouldn’t be anything running on port 80. I ran a Bing search and kb973094 – Error 0x80070020 when you try to start a Web site in IIS 7.0. Although I am using a later version of IIS I still gave it a read because most times things are similar or the same. In the resolution section it said I should run the below in Command Prompt

netstat -aon | find ":80"

With that I would get the output:

and from there I needed to take the Process ID (Last Column) and look in Task Manager. When I opened Task Manager I noticed that the process that was using port 80 was Skype. After Ending the Skype process and doing an IIS Reset everything was back to normal.

I wanted to find out why Skype would be using port 80 and so I went into the settings and noticed a checkbox that was allowing it to use that port:

After un-checking this box Skype has not taken control again.