Process with an ID #### is not running in visual studio professional 2013 update 3

The following steps fix the problem for Visual Studio 2015 and Visual Studio 2017:

• Close VS.
• Navigate to the folder of the solution and delete the hidden .vs folder.
• Restart VS.
• Hit F5 and IIS Express should load as normal, allowing you to debug.

Note: Based on my experience and others in the comments, this problem seems to be caused by moving a project between workstations, environments, or versions of Visual Studio. There must be some environment specific information contained in the .vs folder.

Easily solved:

1. Open Visual Studio as an administrator
2. Right-click your project and click on 'Unload Project'
3. Again, right-click your project and click on 'Edit PROJECT_NAME.csproj'

4. Find the code below and delete it:

   <DevelopmentServerPort>63366</DevelopmentServerPort>
   <DevelopmentServerVPath>/</DevelopmentServerVPath>
   <IISUrl>http://localhost:63366/</IISUrl>
   

5. Save and close the file .csproj

6. Right-click your project and reload it
7. See its working

First Error

For the first error:

Process with an ID #### is not running.

The following steps worked for me:

1. Close all instances of Visual Studio.
2. Rename the IISExpress folder (in my PC is in C:\Users\jmelosegui\Documents).
3. Add the _CSRUN_DISABLE_WORKAROUNDS Environment System variable with the value of 1.
4. Start Visual Studio in administrator mode. (In Windows, right click the executable file and select Run as administrator).

Second Error

The second error:

The webpage is not available

What caused this error:

I deleted IIS Express Development Certificate while playing with the SSL.

The following steps worked for me:

1. Go to Control Panel.
2. Select Add/Remove Programs.
3. Locate IIS 8.0 Express.
4. Right click on it then click Repair.
5. Your certificate should be back!

Hope this helps!