Use double backslashes. Such as in
commands: mkdir C:\\tmp\\
Same for the cacls command, of course. I have just done a test run with my EB configuration and it works. If for some reason this does not work for you, check the following:
- Make sure your .ebextensions*.config files are definitely in the zip file (some zip programs ignore dot-prefixed files by default)
- Make sure that you have SPACES in the configuration file for indentation (not tabs). To be sure, use something like TextPad.
- For other problems I had, I have found good information in
C:\cfn\log
- I assume that you test the creation of the directory by connecting with MSTSC to the instance; if you only test it through your application, some other issues (permissions) may cause the problem.