If you are experiencing this error on OrderCentral it means that you have debugMode enabled. 

1. If you are NOT actively debugging or collecting diagnostic data:
   a. Disable debugMode.

2. If you are actively debugging or collecting diagnostic data:
   a. Verify that the value in web.config key: errorLogFile is valid.
   b. Verify that the errorLogFile is NOT Read-only on the filesystem.
   c. Verify that the "Network Service" local account or "Everyone" has write-access on the filesystem.

Relevant web.config keys:
<!--debugMode:TRUE/FALSE for logging errors to the windows event log or text log file. Default:FALSE--><add key="debugMode" value="TRUE"/>

<!--errorLogFile: if debugMode is TRUE then the system will log error and diagnostic data to the path listed in this key. Note:use double-backslashes -->

<add key="errorLogFile" value="c:\\inetpub\\ctErrorLogs\\ocErrorLog.txt"/>