Too many iterations !
This message occurs if the replacement of a token by another token (recursive tokens) generates more tokens than the value of the Maximum Iterations property, which is set by default to 1000. This message is meant to protect from an accidental infinite loop that could make your workstation freeze. Once this message is generated, Q++ interrupts the processing of the current token, preventing you from having to reboot your workstation.
This message could occur, for example, if some of your user-defined tokens call each other recursively and the replacement string grows and grows without limit. The only cases when this message can occur inappropriately (ie. whene there are no errors in your script) would be when using a very involved [GenTokens] token. In that case you should increase the value of the Maximum Iterations property mentioned above.