Can't view HEIC files?

[JendaLinda]

HEIC requires the HEIF extension and HEVC codecs installed, both are available in Microsoft Store.

[hartlenb]

I've installed the most recent version of 64bit irfanview & plugins files on a Win10 laptop. HEIC files display as a black box. No error message. The filename I'm trying to view is listed on the top irfanview banner. But no image? Help file says HEIC can be viewed with the plugins installed. Any thoughts on what I might be doing wrong?