Garbage collector in c#

Hello everyOne,I am using .net2008 and in c# windows application I am creating first page as splash screen and when i run the application I am getting error as,
" Error 5 Unable to copy file "obj\Debug\myproject.exe" to "bin\Debug\myproject.exe". The process cannot access the file 'bin\Debug\myproject.exe' because it is being used by another process. myproject"
Please help me.I thing this is happen due to splash screen does not remove from memory,what to do to solve  this problem.