Don't simply open the .png file because it's there. MAKE SURE the file was supposed to be sent to you by the sender.
Next, download the attachment from the email to your desktop. If it happens to be malware, your antivirus should find it then. IF nothing goes awry, then Windows already has a program which will open .png picture files. RIGHT click on the file, choose "Open with", then select "Windows Photo Viewer". The picture should open.
If it does not, then the picture is probably corrupt. Or you can try a free photo program called Irfanview from the link below. (It's in the "Imaging Programs" section.) Download the Irfanview installer from the link, then install the program. After it's installed, perform the same steps as above but choose "Irfanview" from the available picture openers.
https://ninite.com/
Hope this helps.
Grif
I received an attachment with an Email marked “image001.png". I have not the faintest idea how to open it and would welcome some advice. Many thanks.

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