下载sax12和x12a.exe程序后，将x12a.exe放在stata的plus文件夹里，按照陈强老师书里的运行命令，为什么会报错，求各位大神指点
. db sax12
. sax12 y, satype(single) inpref(y.spc) outpref(y) transfunc(none) regpre( const td ) outauto( ao ls ) outlsrun(0) ammaxlag
> (2 1) ammaxdiff(2 1) ammaxlead(12) x11mode(add) x11seas(x11default)
x12a.exe not found, please make sure it is under the adopath!