Unfortunately, if the files aren't showing up in Explorer, then the most likely explanation is that they were never written to the card at all for some reason.

A couple of things to check before giving up:

• All modern Canons which can shoot RAW use the .CR2 extension, rather than .CRW.
• The files will be in a different folder from where your Nikon would have placed them - probably "DCIM/100_CANO".

If neither of those work, by all means double check with a card reader, but don't hold out too much hour at this stage.

Unfortunately, if the files aren't showing up in Explorer, then the most likely explanation is that they were never written to the card at all for some reason.

A couple of things to check before giving up:

• All modern Canons which can shoot RAW use the .CR2 extension, rather than .CRW.
• The files will be in a different folder from where your Nikon would have placed them - probably "DCIM/100CANON".

If neither of those work, by all means double check with a card reader, but don't hold out too much hour at this stage.