Are there any issues with verifying the authenticity of ESI?

No. Historically, Intradyn has not experienced any problems with that.

However, dealing with users can always potentially lead to other problems like corruption or other issues with email communications. Fortunately, the archiver can identify and document discoverable issues in an error report, which will indicate any failures with connectivity (emails can’t be “pushed” anywhere) or with mailboxes during the crawler process.