Valid from List & Label 4Error #-23 (LL_ERR_EXPRESSION) indicates that a syntax error has occurred.
In this case, you should try to open the report (project file) in the designer. If the problem could be recognized at that time, you will get an error message from the designer. If not, you should create a Debwin-Logfile (as described in the programmers reference or debwin.txt; since List & Label 16 Self_help.pdf) with following actions:
a) call of the designer
b) printing process
Using variables defined only for the call of the designer, but not for the printing process, is one of the most frequently known reasons for this problem. To solve this problem, please compare the logfiles of action a) and b). Another possibility is to use LlExprError directly after LlPrintStart to get the complete description of the error.
If you want us to help you solving that problem, following information would be necessary:
1) both logfiles ( a) and b) )
2) the project file