IsValid error in advance dupe2? Random?

When pasting a dupe on my server every user gets this error

[AdvDupe2Notify] Pasting…
[AdvDupe2Notify] lua/includes/util.lua:201: attempt to index a string value with bad key (‘IsValid’ is not part of the string library)
Warning: Unhandled usermessage ‘Undone’
[AdvDupe2Notify] Finished Pasting!

Server log doesn’t indicate any errors when the users paste anything either
I don’t understand why this would happen? I assume it’s nothing wrong with adv2 so i’m unsure how to trace the culprit addon and i’m at a loss on how to proceed

Some code is doing IsValid(string_var). Since the error has a custom tag in front, check for any functions called with pcall/xpcall.

Thank you. It was URS doh! Fixed now :slight_smile: