Terrain download not working

[xwind30kts]

I had to do a WASM reset, and was trying to download the terrain data for FS2020. I tried via the OIS in the aircraft, and it is stuck at DOWNLOADING...

In the INI manager there is an error : FAILED TO VERIFY FILE INTEGRITY. 

I have tried restarting the sim and the INI manager many times, ensuring everything is closed, but I still have the same error. 

Let me know how this can be fixed. 

[IniJamir]

So an annoying but possible fix for this is to delete WASM, uninstall the aircraft, restart the PC and then reinstall everything. If that doesn't work, try reinstalling the A350 2-3 times and downloading the terrain data either via manager or in the aircraft. Other users have reported that multiple reinstalls of the aircraft and even reinstalling and relogging into the IniManager have resolved this issue.

Additionally run the Manager in Admin mode when you do.
Let me know if this helps?