c# - Wix bootstrapper How to prevent rollback -

i know if there way prevent rollback when package fail.

like in case have .bat package sets user name , password services. , if fails, want show message @ end of installation telling user need set credential manually. when check credential before installation, , reason failed tell user credential wrong , ask him if wants continue.

(else wouldn't want prevent rollback)

i know there <exitcode/> in <exepackage/> can use prevent rollback, can't detect error value in bootstrapper.

i tried read status in bootstrapper when package complete , return 1 of following:

e.result = result.continue; e.result = result.ignore; e.result = result.ok; 

exemple of reading status:

if (e.status == -2147024895) {     e.result = result.continue; } 

but still rollsback.

i got answer here: http://lists.wixtoolset.org/pipermail/wix-users-wixtoolset.org/

basically, need set package want handle return code vital='no' , in executepackagecomplete handler use e.result = result.ignore; prevent rollback.