[stormer]

You can’t subpoena an object. You could subpoena the administrator, but not the server itself.

[robert14]

So if my car is involved in a hit and run crime, the police cannot take it out of my garage and use it as evidence?

[shalom aleichem]

yes, one may subpena duces tecum.

http://legal-dictionary.thefreedictionary.com/Duces+tecum