For me that's a password.
I say that because we see the special characters (+, /, =)
The "=" sign at the end points to this string being indeed Base64 encoded as it's the character being used for padding the end of Base64 encoded data.
Since decoding the string to UTF-8 or ASCII only leads to gibberish it might be a phrase that's been encrypted before being encoded in Base64. It seems unlikely to be a file not only because of the missing character replacement as pointed out by PawGo, but also because we're looking at 32 bytes of data which is too little for anything except maybe txt files.