The maximum length of memory occupied by the type.

Short strings 255 2-256 are backward compatible.

ANSI is about 2 3 1 4 bytes -2G 8 (ANSI) characters.

WideString is about 2 304 bytes -2G multi-user service and multilingual program.

If a string is simply defined as a string, it may be a short string or an ANSI long string, depending on the value of the $H compilation instruction, and $H+ (default) stands for a long string (ANSIString type). Long strings are strings used by controls in Delphi library.

See if it's a compilation instruction problem.