ERROR 29-185: Width Specified for format ---- is invalid

You see "ERROR 29-185: Width Specified for format ----  is invalid" message in the log file  when you try to specify the DATE format but used an invalid width. DATE format will not result in a date if it is too long or too short. Valid values are 5-9 in SAS 9.1.X versions. If you use newer version (SAS 9.2) then you won't see this Error message in the log. ( I am assuming that this is fixed in SAS 9.2).

Try using format date9. instead of date11. if you are using SAS 9.1.x (either Windows or Unix) version.

data _null_;
date ='23-SEP-2004'd;
put date date11.;*This statement gives you error in SAS 9.1.2/9.1.3 versions;
put date date9.;
run;