It turns out the cause of my issue was another rex statement down the line that hadn't been updated to match the renamed string. It used  (?<Foo>\D\d*)-0 which matched the string before the replacement, which the statement is now (?<Foo>\D*\d)-0 Apologies for my confusion. I've marked your efforts as the solution as the backslash was indeed not needed. Thank you and have some Karma for your efforts. ... View more

Yeah I tried that first, but other related issues on the boards led me to try it with the backslash. It returns the same results. ... View more