Hello, I had posted the same question a while ago and I got a very good response from the community asking me to change the JRE version as the application I was testing used a later version. I followed the instructions provided an switched the JRE version that NeoLoad uses to JRE1.8 (I was warned that NeoLoad may not behave well). I tried recording the script and I got the same error but the details are different. I have attached the details of the error to this message.
It's difficult to say what the root cause could be with only the error details. Do you know if the developers of the application modified the default GWT method?
For example it often happens that they modify the format of the date in GWT. Are you aware of such modifications?
What is the GWT version used by your application?