memory violation : Exception ACCESS_VIOLATION received.

I am getting an memory ACCESS_VIOLATION exception; LoadRunner Version 11.52; execution aborts after this line and goes to vuser_end.c; Logging is full but no other message is displayed; size of array varis from 6 to 50. 

The code looks like 

extern char *strcat( char *to, const char *from );

...

...

lr_save_string(strcat(" or CategorizationID eq ", lr_paramarr_idx("CatalogItemFieldValuesNames", n - 1)), "ifCategorization");

Exception:

Action.c(211): Error: C interpreter run time error: Action.c (211):  Error -- memory violation : Exception ACCESS_VIOLATION received.