Downloaded jpg images will not open

[RenaissanceMan]

Downloaded jpg images often result in "Format of the file <filename.jpg> could not be determined For displaying of less common formats, the following option is available: Options> General>[x] Display all image file types"

Thumbnail cache cleared
Program reinstalled
Ini file renamed
I DO have Display all image file types checked.

I can open the image in IrfanView; if I then save it in the same jpg format, the saved image will then open in XnView Classic.

Why is this happening and how can I fix it?

I'm running v. 2.52.0 & Windows 11 24H2

[cday]

Best to post an example JPEG file that doesn't open in XnView software, if necessary in a ZIP archive, forum maximum attachment size 2MiB, otherwise you could provide a download link.

[RenaissanceMan]

Attached is the image in a zip file

[cday]

Probably not actually a JPEG, changing the extension it doesn't seem to be a PNG, I think Irfanview has an option to open incorrectly formed files, doesn't it?

[XnTriq]

white-wine-day.jpg is actually an AVIF.
This format is not supported by XnView Classic.
But XnView MP can read (and write) them.

[XnTriq]

Many content management systems convert JPEGs and PNGs on websites to WebP or AVIF without changing the filename extension.

XnView MP:

1. Go to Tools → Settings… → File list
2. Deactivate Recognize only by extension.
3. Set Scan file headers to Always