I was in the process of updating Suppliers - adding comments relating to delivery costs etc. Almost all went through perfectly, but there was 1 that contained
“20kgs @ 5100 p/kg”
This caused “Encryption key is invalid, Please check site_config.json” (I obviously had not made any changes to that file).
I edited to “20kgs at 5100 p/kg” - and then it went through without any trouble.
I did check the charset etc and there seems to be nothing in there which would cause an issue.
I also tried to create a comment which contained ONLY
“@”
Same error occurred (implies some sort of escaping is needed?? but I am not a programmer 
On the other side of the spectrum, including an email address in the comments seems to be OK - it’s just when the character is between whitespaces that it isn’t happy
- Is this a normal/expected behaviour?
- The “problem” is solved - but I am just curious