Unsuccessful in changing modify date for MP4 files

[ohrmc]

What a fantastic program this is. I successfully modified the create/modify dates for the few thousand pictures that were copied over to another drive. But I'm unsuccessful with the video files.

I issued the command: Z:\exiftool -r "-DateTimeOriginal>FileModifyDate" Z:\Pictures\

And I received the following warning for just the .mp4 files

"Warning: No writable tags set from Z:/Pictures/...' where "..." is the name of the mp4 file. I received this warning for every mp4 file.

Admittedly, I'm trying to get a quick fix for this. Would anyone have a few moments to let me know commands would work?

Thanks so much.

[Phil Harvey]

Typically videos don't contain DateTimeOriginal.  Try CreateDate instead.

- Phil

[StarGeek]

Use this command to see all the time stamps in the file
exiftool -time:all -G1 -a -s /path/to/files/

Also note that most time stamps in a video are supposed to be set to UTC and the program reading them is supposed to adjust the data to the local time zone when displaying it. So the time stamps you see might be off by the time zone, as exiftool shows the raw value unless you use the -api QuickTimeUTC option.

[ohrmc]

Typically videos don't contain DateTimeOriginal.  Try CreateDate instead.

- Phil

Worked perfectly. Thanks so much for your time. And for the program!

[ohrmc]

Use this command to see all the time stamps in the file
exiftool -time:all -G1 -a -s /path/to/files/

Also note that most time stamps in a video are supposed to be set to UTC and the program reading them is supposed to adjust the data to the local time zone when displaying it. So the time stamps you see might be off by the time zone, as exiftool shows the raw value unless you use the -api QuickTimeUTC option.

Thank you!