I am using sas 9.2 server (os is 64bit) to import the excel file (.xlsx format)

When I use the import procedure, it works,

PROC IMPORT OUT= WORK.aa
            DATAFILE= "...\aa.xlsx"
            DBMS=EXCELCS REPLACE;
     RANGE="Sheet1$";
     SCANTEXT=YES;
     USEDATE=YES;
     SCANTIME=YES;
RUN;

But when I use the libname statement, I get the error message as below,

libname aa excelcs "...\aa.xlsx";

ERROR: The EXCELCS engine cannot be found.
ERROR: Error in the LIBNAME statement.

Could someone help me to solve the issue? Thank!