When saving the settings using Tools->Options you may see an error: "Cannot create a file when that file already exists."
This is typically due to your anti-virus program or security permissions.
Specifically, we have seen error when McAfee Real-Time Scanner is active.
To resolve this issue, add the following file to the Excluded File list in the Anti-virus software:
%APPDATA%\Liquid Technologies Ltd\Liquid XML Studio 2015\UserSettings.xml
But also check that your account has read/write access to the containing folder
%APPDATA%\Liquid Technologies Ltd