Have you tried the DISM command? (https://www.windowscentral.com/how-use-dism-command-line-utility-repair-windows-10-image)

Thanks for that. It looks a bit advanced for a beginner like me, but I will have a careful look through.

I got a good reply from DELL directly telling me how to uninstall Edge and reinstall in and I could follow that, though it didn't work.

I would try running DISM multiple times then retrying an Edge reinstall. Also could you post the instructions they sent you?

When I first tried to post the above I was an invalid HTML had been removed but I can't see it.

Yes definitely DISM should be run before attempting to reinstall Edge using their method. I would try uninstalling Edge by using the method in this link (https://www.windowscentral.com/how-remove-microsoft-edge-windows-10). Then reinstalling it through the Windows store.

Great, thanks.

These were the instructions:

• Uninstall reinstall MS Edge: 
1. Right click on Windows icon and select RUN.
2. Type C:\Users\%username%\AppData\Local\Packages\Microsoft.MicrosoftEdge_8wekyb3d8bbwe
3. Hit Enter key
4. Once the folder opens, press the Ctrl + A keys to select all the folders in the current window.
5. Press the Delete key on the keyboard. If a confirmation box opens, select “Yes“.
6. Close the window.
 
• Reinstall MS Edge: 
1. Open Windows/Cortana search box
2. Type PowerShell -> Right click on PowerShell in the list and click on Run as Administrator
3. Now type the following in the PowerShell window and press Enter.
Get-AppXPackage -AllUsers -Name Microsoft.MicrosoftEdge | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register "$($_.InstallLocation)\AppXManifest.xml" -Verbose}
4. After it is done, close the PowerShell window.
5. Restart the computer, check if the MS Edge browser works fine. 

I've just had an email about a new reply but I can't see it.

Thanks.

I did something with DISM but I'll give it another go.