Hi Abiodun Olatunbosun I deploy the Web Screens extensively - we have a  demo site at https://sage300demo.accsysconsulting.com.au:4433/Sage300 and have come across "HRESULT E_FAIL" but not the ...has been returned from a call to a COM component".  This last bit of the error sounds key, so I would first check:

Note:  The screenshots below are from a basic test system for troubleshooting and show non-recommended shortcuts like using the SQL SA account for databases.  Don't copy these lazy steps in your production environment!

• Make sure you had the correct IIS components deployed as per the manual before installing/repairing:
  
• You can log into the Sage 300 classic desktop screens on the Application Server without error.  This is critical as if the Classic screens don't work, the Web Screens won't work.
• The Sage.CNA.WindowService service is up and running without issue
  
• Your Portal Database looks healthy when propagated:
  
• Check if your API screen is working and if that produces any errors as it doesn't even require a login https://<server>/Sage300WebAPI i.e. https://sage300demo.accsysconsulting.com.au:4433/Sage300WebAPI
• Make sure the local IIS_IUSERS has permissions to your Online folder i.e.:
  
• Make sure your SSL certificate matches the server name you're using to access the server i.e.:
  
• Also the documentation is excellent!
  
  
  • • Use the Install Guide for configuring web components and installing the Web Screens - see Chapter 2 for IIS components and Chapter 5 for configuring the Web Screens.

Check these first and if they don't lead you to the issue let me know where you get up to and I'll assist further.

Cheers...Tim