Archive Distribution Fails to Run on macOS 10.12 (Sierra)

Problem

For versions prior to 18.1, the classic archive distributions of Oxygen XML Editor (.zip or .tar.gz) fail to run on macOS 10.12 (Sierra).

Cause

This happens because the archives get quarantined and macOS 10.12 (Sierra) treats quarantined apps differently than older versions and isolates them from their parent folder at launch. If Oxygen XML Editor was already installed when you upgraded to macOS 10.12 (Sierra), there are no problems.

Solution

If Oxygen XML Editor was not already installed, or you need to reinstall an older version (prior to version 18.1), the quarantine flag must be removed for the entire content of the Oxygen XML Editor installation directory or the individual applications. To resolve this issue, follow these steps:

Open a Terminal window and change the directory to the folder where Oxygen XML Editor is located.
Run the following command:
```
xattr -dr com.apple.quarantine oxygen/
```
where "oxygen" is the actual name of the Oxygen XML Editor directory.

If Oxygen XML Editor is in a location that requires administrator privileges for write access, you need to run the command from an administrator account and prefix the command with sudo. You will then be prompted to enter your password.