Invalid use of vertical bars in query expression

I'm trying to insert a record into a memo field of an Access database. The record contains vertical bars (| |). I get an error message of
Err 3075
Invalid use of vertical bars in query expression.

I can't find any mention of vertical bars being a problem. Anybody know the right answer?

TIA
Bash

Vertical bars are reserved in SQL to concatinate two strings together. To refer to them as characters and not directives try preceding them with backslashes.

Thanks... I was aware the | | did concatenation for other DB engines, but was unaware of it being a problem in Access. I did finally find mention of the usage in the help files in the Use values in expressions topic. Thanx