You need to check in the extension for ePO 4.x. In the package you'll find a zip file called VSESTOMD1000.zip - check this in, and that will give you the ability to create policies.
Fantastic - thanks Joe! I'd seen that zip file in the package but had tried to check it into the repository, rather than install as an extension ...
Has anybody managed to add Virus Scan for Storage package to 4.6 EPO ? I am able to add VSESTOMD1020.zip (I suppose it's newest version), but no policies appear in policies tab