API [Salesforce SDK]: Invalid Crypto Key

When following the instructions for instantiating/creating a new API connection to Box with the Box for Salesforce SDK, the following error message can be returned:

System.SecurityException: Invalid Crypto Key

Environment

Box for Salesforce SDK

Steps To Resolve

Verify that the private key has been properly formatted and decrypted.

1. Copy/pasted the encrypted private key from the downloaded .json into a new .pem document
2. Leave in "-----BEGIN ENCRYPTED PRIVATE KEY-----" and "-----END ENCRYPTED PRIVATE KEY-----" at the top and bottom, respectively, each on their own lines
3. For the encoded certificate, make a new line every 65 characters
4. In a UNIX terminal (Macs), run the code openssl pkcs8 -topk8 -nocrypt -in your_private_key.pem -outform PEM
5. Terminal then prompts for the private key passphrase (found the .json file)
6. A decoded private key is returned.
7. Copy all content between the begin/end terms into a single line for "YOUR_PRIVATE_KEY".

Root Cause

Improperly formatted or decrypted private key.