Some CF cards don't have much of a "lip" on the end, making it difficult to remove using a fingernail. I have this issue with my Fujitsu Stylistic CT2020, and Fujitsu supposedly provided a small supply of what they called "H-tabs," which were stickers shaped like an H that one could attach folded in half to the front and back face of the CF card along the edge, creating a pull tab for the card. You could improvise and make a tab yourself using some kind of tape with a strong adhesive, like packaging tape.
(Don't use standard cellophane tape; it won't hold.
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