How would I solve a string whereof I don't know the decryption (cipher) from?

Question

I had tried using this site to decode it, but alas. This is the cipher I\'m trying to decode;

akkk/+IExVYIdxOeAkupimS3RDkJxIZjgXHiJx/Kl6KsKG7lsbtBWw6996y