File->Properties->Details->Missing dates

Just curious to know as to why files are missing creation/modified dates under 'Properties->tab Details'
This is not Opus restricted: Windows Explorer does not show dates either. That's why I am posting here.
It is just a minor thing, but am wondering why though.
Maybe there is a logical explanation for it.

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In both programs, the Properties dialog comes from Windows not Opus.

My guess is the Properties dialog doesn't display dates if they are outside a certain range, as it assumes they are invalid (or it may use an internal date format which cannot represent such dates, e.g. dates before 1970 perhaps).

Is that .txt file really last modified in 1967, or is the datestamp random data?

Thanks Leo. I know this has nothing to do with Opus (as said, reason why I posted in 'Off-topic' area)
I went on testing with re-dating files and discovered that files prior 1980 showed this habit, i.e. empty creation / modified fields.
Searched on Internet and found that there is 'something' with pre 01-01-1980 dates.
Has something to do with the old FAT system, see: https://blogs.msdn.microsoft.com/oldnewthing/20161108-00/?p=94665

Solved.

Thanks again.