Why is OS X giving me a warning about installing apps when I try to open an XML file with Webstorm? I've extracted some XML files from an email attachment. I would like to open them in Webstorm instead of Xcode. But when I try to use the "Open With -> Other" and pick Webstorm, I get a message about being unable to install the app. That doesn't make any sense, since xml files are just text. Screenshots: 




Are XML files somehow defined as apps by OS X? Is there a way to change that? Is this a bug? 

I have verified that the file is just xml and it can be opened by WebStorm with no issues. This seems to be a Finder/security issue.
Open Terminal and type xattr -rd com.apple.quarantine followed by a space, then drag the file or folder of files that you can't open directly into the Terminal window, and push return. You should now be able to open the file directly.