
Field size deviates from legal range [1~254]
You have tried to add a new userdefined field. In the Field Data window, you have selected in the Type field, the value Alphanumeric. In the Length field, you have entered a number that is either less than 1 or greater than 254, and chosen Add.
You can set the length of a userdefined field of type alphanumeric to be between 1 and 254 characters.