Thanks for your feedback and using Aspose.Cells for GridWeb.
Please note these settings in web.config file, this is important. Check the red color part. It is the path of acw_client directory which is necessary for GridWeb to work. It contains the acwmain.js and other resource files which are important for Aspose.Cells.GridWeb to work properly. For example, you may add a folder named grid in your project and then add the acw_client directory (you may copy it from your your installation directory, e.g “…Aspose\Aspose.Cells for .NET”). Now add the following lines to web.config file:
<add key="aspose.cells.gridweb.acw_client_path" value="grid/acw_client/"/>
<add key="aspose.cells.gridweb.force_script_path" value="true"/>
<add key="aspose.cells.gridweb.forcepath" value="true"/>
Hopefully, this information will help you in sorting out this issue.
If you still find the issue, kindly do create a simple project (runnable) using latest Aspose.Cells.GridWeb v19.1.x with its resource files, zip the project and post us here, we will check it soon.