11. A computer-readable medium having stored thereon computer-executable components that, in response to execution, cause a computing device to perform operations including: based on content of a received message including a document and an encrypted access code, generating an image having embedded information that includes the encrypted access code; capturing a copy of the image; decrypting the encrypted access code from the copy of the image using stored information to yield a decrypted access code; and generating an output that includes the decrypted access code, the output allowing access to the document.
11. A computer-readable medium having stored thereon computer-executable components that, in response to execution, cause a computing device to perform operations including: based on content of a received message including a document and an encrypted access code, generating an image having embedded information that includes the encrypted access code; capturing a copy of the image; decrypting the encrypted access code from the copy of the image using stored information to yield a decrypted access code; and generating an output that includes the decrypted access code, the output allowing access to the document. 15. The computer-readable medium of claim 11 , wherein the decrypting includes decrypting the encrypted access code using a cryptographic algorithm.