Too many levels of token iteration !
This message occurs if the conversion of a given token (noted in the message title) generates yet more tokens and this happens more than 1000 times for the same token. It means that one of your tokens is replaced by another token, then that token is replaced by yet another token, and so on ... 1000 times or more.
This is usually a sign that you are replacing a token by the same token in the Tokens Manager.
This message can also occur in diaries that contain macros that call each other, particularly those that generate complex multi-month diaries from a very simple GridTemplate (such as is the case below) :
In those cases it can happen that this message is generated even though there is no danger of an infinite loop. You can tell this is the case because the conversion of tokens will proceed properly and stop at a specific place,as can be seen in the example below :
In those cases you should increase the value of Maximum Iterations.