How can I know what part of RTF syntax is wrong

Question

an RTF is getting built and passed into some methods and finally getting passed to a text editor but something is wrong because the editor cannot parse it and instead of the correct text - NewYork in this case- it will show the whole rtf text but I have problem with finding out what is actually wrong with this RTF so maybe I can narrow it down and find out where is the place in code that is messing up the rtf tags, in my example it looks like this:

"{\rt\plain\f0\fs24 f1\ansi\deff0{\fonttbl{\f0\fswiss Microsoft Sans Serif;}{\f1\fswiss Tahoma;}}\deflang2057\deflange2057 \plain \f0 \fs24 \cb2 NewYork \plain \f0 \fs24 \cb2}"

Answer 1

Should start with \rtf1 and you had a stray f1 that should have been \f1.

{\rtf1\plain\f0\fs24 \f1\ansi\deff0{\fonttbl{\f0\fswiss Microsoft Sans Serif;}{\f1\fswiss Tahoma;}}\deflang2057\deflange2057 \plain \f0 \fs24 \cb2 NewYork \plain \f0 \fs24 \cb2}"