Is your paper wallet a private-key (weird big string) or a backup seed (list of words)?
To clarify your private key can look like any of the following:
Base58 uncompressed private key (note the first character)
5Kb8kLf9zgWQnogidDA76MzPL6TsZZY36hWXMssSzNydYXYB9KF
Can be imported in any wallet that has the import option
Base58 compressed private key (note the first character it can also be K)
L53fCHmQhbNp1B4JipfBtfeHZH7cAibzG9oK19XfiFzxHgAkz6JK
Can be imported in any wallet that has the import option
Hexadecimal private key (note the length is 64 and characters are 0-9 and a-f)
E9873D79C6D87DC0FB6A5778633389F4453213303DA61F20BD67FC233AA33262
Has to be converted to a base58 (WIF) private key like the 2 examples above before the wallets accept it. To do that you could use this open source tool:
https://github.com/pointbiz/bitaddress.org (run offline)
Base58 encrypted private key using BIP38 (note the first 2 characters)
6PRW8vhrsbZJdZDtVCKtfnPoN7ecWKraUagCDg7M9APkNGMxx3fbwMkysT
In this case you also must have the password that were used to encrypt this key and some wallets don't accept this type so it has to be decrypted first before you can import it in a wallet. You can use the bitaddress.org tool to decrypt it.
Password used here is "123" in case you want to test decrypting in that tool.