This is a standard change, documented and supported by Cognos.
1) Using Cognos Configuration, stop Cognos 8.
2) Rename the File Name: <install location>\templates\ps\async\system.xml.sample file to system.xml.
3) Using Cognos Configuration, start Cognos 8.
Tip: To restore the regular mode, delete the File Name: <install location>\templates\ps\async\system.xml file.
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