https://stackoverflow.com/questions/8925323/redirection-of-standard-and-error-output-appending-to-the-same-log-file
The second way would look like this:
& myjob.bat 2>&1 >> C:\MyLog.txt
Or this:
& myjob.bat 2>&1 | Out-File C:\MyLog.txt -Append
powershell输出错误信息到文件
原文：http://www.cnblogs.com/chucklu/p/7602885.html
