connect2vishal,
Sorry that you ran into this issue. I could not replicate the issue on MyEclipse 9.
Can you answer some more questions for me to understand the issue better ?
1) Which version of ME did you try ? Share the build id from Help > About MyEclipse Enterprise Workbench> Build Id. Paste it here.
2) How did you install the GWT plugin and which version ? Is it through the Quick Add Popular plugins or through an Update Site ?. If its an Update site, then please share the link.
3) What exact error/behavior did you see when creating the HTML file ? Check for any errors of interest logged in the .log file which is located at <workspace dir>/.metadata/.log. Paste the errors here.
4) Can you attach a screenshot of the IDE when you try creating a new html file ? Here is an FAQ about how to attach the files :
https://www.genuitec.com/forums/topic/troubleshooting-how-to-upload-attachments-on-forum/