When using the cfwindow tag an error is thrown:

There was an error while validation.
For more details check logs.

The stack trace will include:

coldfusion.security.ESAPIUtils$ValidationUtilExcep tion: There was an error while validation.

Research & Resolution:

Details on this error can be found in: {cfroot}/logs/esapi.log

If you receive the following error in the log, make sure your TITLE tag in the cfwindow tag meets the required regex expression.
CFContainerID: Invalid input. Please conform to regex ^[\p{Alnum}_\-\.:]+$ with a maximum length of 100
This new validation was include as part of the APSB11-14