An example of a Newton error would be -48002, which is 'store format is too old to understand'. Ignore the -4, as far as I know it currently has no meaning except to be there. The '80' part of the number is the error type, which would be 'Store Errors'. These are listed in the 'Error Type' section. The '002' is the error number that specifically identifies what the error is. These are listed in the 'Error Number' section. Put the two together and you're on a roll... Error Type 80 Store Error 82 Object System Error 84 Bad Type Error 88 Interpreter Error Error Number 2 store format is too old to understand 3 store format is too new to understand 4 store is corrupted, cannot recover 5 single object is corrupted, cannot recover 9 not a soup entry 10 tried to remove a store that was not registered 11 soup index has an unknown type 12 soup index has an unknown key structure 13 soup index does not exist 14 a soup with this name already exists 15 tried to CopyEntries to an unknown soup 16 soup is invalid 17 soup is invalid 18 entry is invalid 19 key does not have the type specified in the index 20 store is in ROM 21 soup already has an index with this path 22 internal error 23 tried to call RemoveIndex on the _uniqueID index 24 queary type missing or unknown 25 discovered index inconsistency 200 expected frame, array, or binary object, but got something else 202 empty path 203 invalid segment in path 204 path failed 205 index out of bounds (string or array) 206 source and destination must be different objects 207 long out of range (too large or small) 210 bad arguments 211 string too big 214 object is read-only 215 functionality is unimplemented 400 expected a frame 401 expected an array 402 expected a string 403 expected a pointer 404 expected a number 405 expected a real 406 expected an integer 407 expected a character 408 expected a binary object 409 expected a path expression, symbol or integer 410 expected a symbol 411 expected a symbol 412 expected a fram or an array 413 expected an array or NIL 414 expected a string or NIL 415 expected a binary object or NIL 416 unexpected frame 417 unexpected binary object 418 unexpected immediate 499 unexpected Spanish Inquisition 800 not in a break loop, but presumably called break 802 too many arguments for a CFunction 803 wrong number of arguments 804 FOR loop BY expression has value zero 806 no current exception 807 undefined variable 808 undefined global function 809 undefined method 810 no _proto for inherited send 811 tried to access slot in NIL context 814 local variables and FOR/WITH loops are not allowed at top level