VB.NET Process.Start failing

Question

A problem that has been plaguing me for nearly a week now.

I am trying to get an install of IIS to take place through the command line in VB. I understand that i need to be setting up an Unattended xml script to call, but here is a fundamental bit that is confusing me:

If i run the command : ' start /w pkgmgr /iu:IIS-WebServerRole;IIS-WebServer; ' it executes perfectly within CMD.exe.

If i add the command to a batch file and run the batch file, it runs perfectly.

If i call the command using : Dim myProcess As Process = Process.Start("cmd.exe", "/k start /w pkgmgr /iu:IIS-WebServerRole;IIS-WebServer;"), then it fails with an error of:

////////////////////////////////////////////////////////////////////////////////////////////////////////////
                    Operation failed with 0x8007000B                             ////
                                                                                                      ////
An attempt was made to run the program in an incorrect format ////
////////////////////////////////////////////////////////////////////////////////////////////////////////

If i call the batch file mentioned earlier, then i get the exact same error.

How can it work perfectly with the two first examples but fail when it is called through VB?

Thanks for any help!

Answer 1

Your VB.NET program is very likely to be running in 32-bit mode and will start the 32-bit version of cmd.exe. The one from c:\windows\syswow64 instead of the one from c:\windows\system32 that you used before. Getting BadImageFormatException starts to become likely.

Project + Properties, Compile tab, set the Target CPU to AnyCPU and untick the "Prefer 32-bit" option. On older versions of VS click the Advanced Compile Options button to get to the setting.