The same logfile error was reported in RE: Put content of variable into XOG message (but no explanation). That "prolog" error message occurs (in a different scenario) when a strange/non-ascii text editor has been used to edit an XML script - this might be related??? (Search for 'prolog' on the forums for more details).
That is typically about the structure and syntax of your xml file.
Try opening the file with a browser, it may display info about the error and the location/line number.
If not post your file here.
I would suggest you to perform the following steps: a. login to Clarity application as an admin user b. modify URL to: http://<svr>/niku/nu#action:security.caches c. click Caches tab, click FLUSH ALL button d. click Groups tab, click FLUSH ALL button e. logout f. login and check if problem persists. g. if problem persists, restart all APPs
Note: Clear the Caches when the user load is minimum, Downtime is not needed though. As the activity may close all the active sessions.
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