Thanks Lee16 and DavidR and Eddy’s earlier response,
Following your suggestion re firewall I looked in the taskbar to find Sygate not there, so I went into start programmes and opened
Sygate.
As soon as I opened it screens came up asking me to allow the various avast programmes, followed by avast pop up telling me of virus update.
All updated now Thanks again to you All.
Best regards Mal76