Hello,
We've just released a hotfix for Windows Media Encoder running under Vista. There's no need to install it under XP or other version of Windows. It addresses the following symptoms:
Issue 1
When you run the Windows Media Encoder command-line script WMCmd.vbs, the script host Cscript.exe may crash.
Issue 2
The icons that appear on the encoder toolbar and in the encoder dialog boxes are displayed by using a low bit depth. Therefore, the icons appear to have a low resolution.
Issue 3
When you configure the encoding profile or start an encoding session, the encoder may crash.
The KB article and hotfix download are here:
https://support.microsoft.com/default.aspx/kb/929182