Honest - that is what the error message said.
Then it said "error type: InvalidUrlHashError"
It was a short test file. Just signed up for this and need Whisply to make it work for what I need.
I encrypted the file, right clicked, Got to Whisply, chose the option with a PIN, got the link. Then I copied the link and pasted it into my normal email account.
The link came through but when I clicked on it, I received the above error.
Tried it three times.