Today I installed VS2010 SP1 Beta, and IIS 7 Express, as I currently have IIS5 on my local development machine and thought I'd try IIS Express out.
I have gone into the properties window for my Web Application, checked the 'Use IIS Express' checkbox, created the Virtual Directory when it has prompted me, but then get the message "Unable to launch the IIS Express Web Server. Port x is in use".
I have tried changing the port number from the default value that was in there, to numerous other port numbers, but whatever value is there, I am always getting this message, and am therefore unable to use the IIS Express Web Server.
Does anyone know what the problem might be, and how to get around it?
If you are using ESET NOD32 Anti Virus, you need to change the setting of "Web access protection" => HTTP, HTTPS => Web browsers => red cross the check box of your devnev.exe (This is three state checkboxs, click the check box until red cross appeared)
I have just installed VS 2010 SP1, using the above setting to tell NOD32 to leave 'IIS Express' alone.
What version OS are you using? Are you able to start IIS Express from command line? Could you try the following and post the error message you are seeing.
Remove IISExpress directory located under 'My documents' folder
Go to IIS Express installation folder '%programfiles%\IIS Express' (on 64-bit machine '%programfiles(x86)\IIS Express') and try to start iisexpress.exe from command line (without passing any arguments)
I had a similar problem. It seems that if IIS Express is already running a particular site and then you try to run a project that uses that site through Visual Studio it isn't able to attach the debugger. The solution was to close any running instances of IIS Express and WebMatrix and then try running the site through Visual Studio (F5).
I recommend installing WebMatrix as it's the simplest way of managing the sites and port numbers that you are using.
I have the same problem in the visual studio 2012.
I am creating a sharepoint app for the SharePoint 2013 and it happened after some days means it was working before then I got the error:
" Unable to Launch IIS web Server " "port 62308 in use.
To fix this I just went to the settings of the web project by right clicking on the project node in in right panel under the project solution tab. Change the port number and configure the virtual directory and it worked for me.
Hope it work for anyone else in case he/she has any problem.
1- Close Visual Studio.
2- Delete IIS Express folder in Documents or edit applicationhost.config:
<bindings>
<binding protocol="http" bindingInformation=":8080:localhost" />
</bindings>
3- Delete solution file.
4- Start Visual Studio and use open website.
5- Choose your website folder.
You may uninstall IIS 5, or simply configure your IIS 5 web site to use a port other than 80.
IIS Express tries to use port 80, which leads to the conflict.
If any body still facing the same issue ... even after trying all the above steps try the following simple steps...
1) close all other applications
2) Download TcpView application from
http://technet.microsoft.com/en-gb/sysinternals/bb897437.aspx
3) run the application, check the localport column and see who is using that specific port and end that task
That will solve your problem ... :)
go to solution explorer, right click on the present Application then go to properties, now click on web scroll the mouse and change the port no. from project localhost:1257 NOW RUN IT...
来源：https://stackoverflow.com/questions/4968804/iis-express-web-server-every-port-is-in-use