Basic PAYE Tools not appearing on screen

I have used BPT for many years. For the first time I cannot use it this month. The icon is on my (usual) PC desktop . When I click it nothing appears on onscreen When I hover over the pinned icon I see "Basic Paye Tools-RTI" above blankness. If i click and hold the icon and then release I see a white blank box disappear very quickly to the right..as if heading for another screen. Does anyone have any theories on what is happening or what I can do? The PC is 5 or 6 years old but no other piece of software has failed recently. Thank you Tim

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