[Anonymous]

Try running the script on an alternate machine first thing in the morning. Copy the file, run the script, does the same error present itself? This will either identify or eliminate the script pc as the issue. You may want to look at the Application and Security event logs for the times when the error occurred as an additional troubleshooting tip. Sometimes additional information is available that will identify the cause.

Have you thought of adding additional error handling? What step generates the error?