Marcus:D

Hey guys, I was playing some tekkit and decided to switch over to my other world on tekkit clasic(its been a long time since ive played on that world) and then when i pick up any blocks mining or anything it says this error in the chat. InvTweaks : Error while loading config: Invalid byte 1 of 1-byte UTF-8 sequence. Anyone know how to fix this? ive tried uninstalling the pack and eveything, thanks for the help