Symptom:

Upon logoff from a SoftXpand workstation an error message appears displaying Mixer error.

Cause:

This error may exist when using audio devices (ATI video cards with audio, or PCI CMedia cards) drivers that also include a ‘mixer’ application which tries to load at PC and workstation startup.
This startup application is blocked by SoftXpand and cannot load.

Solution:

In order to eliminate the error message from appearing, use msconfig, to cancel the loading of the mixer application at startup.

• Click on Start – Run and type msconfig.
• On startup tab, uncheck the Mixer checkbox.
  
  
  
  
• Restart the PC.
  After the PC has restarted a message will appear indicating that some system configuration has been changed. Select the ‘Don’t show this message again’ checkbox, and click ‘OK’.

Note: other startup management applications may be used to do the same.
Such as: SysInternals autoruns and more.