clearer error message as to why key is not usable #5032
Description
User is getting This OpenPGP key is not usable. which doesn't say much, but we do seem to have access to the actual problem as visible from compatibility test:
(14) PK 0 > Encrypt/Decrypt test: Got error performing encryption/decryption test: Error: Error encrypting message: Could not find valid encryption key packet in key 87e87b1cf73b7e44: elgamal keys are considered too weak.:
The error message could be clearer, so we could say eg Could not find valid encryption key packet in key 87e87b1cf73b7e44: elgamal keys are considered too weak. instead of This OpenPGP key is not usable. when importing (or wherever that error was originally encountered.
Originally posted by @tomholub in #5030 (comment)