exe file not installing properly from msi

Question

I am trying to build a msi file using Visual Studio 2013 (VSI bundle) with 3 exe files.

1. 7z file for unzip zip files which is also included in msi
2. openvpn exe file
3. automate.exe, which is basically a bat file converted in exe file.

Now in 3rd file I faced an issue. After setting an environment variable by the msi package 1 and 2 successfully executed. but in 3rd 7z command not working, but if I run automate.exe individually it works perfectly.

How can I solve this issue? I add those exe in custom action in VSI.