When you try to start a web site in IIS, you may receive the popup error “The process cannot access the file because it is being used by another process”. In the system event log event ID 1004 and 15005 will have been generated stating that they cannot register or bind to the port number that the web site is assigned. 

To find which process is conflicting run the following commands:

netstat -anop TCP|find “:<port #> “

Match the PID with the process name;

tasklist /SVC /FI “PID eq <process ID #returned from 1st command>″

Here is a sample:

C:\Documents and Settings\MOSSfarm>netstat -anop TCP|find ":8080"

  TCP    0.0.0.0:8080           0.0.0.0:0              LISTENING       1336

C:\Documents and Settings\MOSSfarm>tasklist /SVC /FI "PID eq 1336"

Image Name                     PID Services

========================= ======== ============================================

miniwinagent.exe              1336 miniwinagent

With this information you can determine if you can stop or change the blocking process or if you need to use another port for your web site.