Well i generated a keypair with openssl
openssl genrsa -des3 -out _private.pem 1024
openssl rsa -pubout -in _private.pem -out public.pem
P
In my experience, LockBox 3 needs a PKCS#1 public key when working with OpenSSL generated keys. You must convert the public key to PKCS#1 before Lockbox3 can load it. (OpenSSL generates a PKCS#8 key). Use the RSAPublicKey keyword.
openssl rsa -pubin -in yourpublickey -RSAPublicKey_out -out publicpkcs1
https://www.openssl.org/docs/apps/rsa.html
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