How to unforget SD card?

SD readers do not end to have a spring to fling the device across your desk. So the drive would seem to be 'forgotten' after a successful 'eject'.

To read it again, you must completely remove the ejected drive, wait a short while, then re-insert it again later. if no joy, restart your Mac and try again.

I am not familiar with any command in any Application resembling "forget".

¿What were you running, and what command did you choose to accomplish "forget" ??

Hi,

If you mean you initialized SD card, I think you can't salvage data on SD card.