OS> I think that mode 13 is free for use, between WF_NEXTXYWH(12) and OS> WF_NEWDESK(14). Anyone know if this mode is used for anything? It looks like that mode 13 is used. I found a message from Martin Osieka (Autthor from WINX, MiNA). He wrote that some old AES version use this mode for wind_set. Now I know why in all headers is a define like #define WF_IGNORE 13 or #define WF_RESVD 13 Gerhard