Hi marilynr,
The regsvr32 command can fail if the dll file you are trying to register is not placed in the correct location. While running the regsvr32 command, make sure that the mpexp.dll file is at the location “c:\example\mpexp.dll”
Media Info Exporter is a part of Windows Media Player 9 Series Winter Fun Pack.
Windows Media Player 9 Series Winter Fun Pack is not compatible with Windows Vista as mentioned in the following site.
However, you can try running the downloaded program in compatibility mode for Windows XP.
Make older programs run in this version of Windows
http://windowshelp.microsoft.com/Windows/en-US/help/bf416877-c83f-4476-a3da-8ec98dcf5f101033.mspx
Thanks and Regards,
Gulrez
Microsoft Answers Support Engineer