iCloud64.msi fix?!?!?!?

Tried to update iTunes and get the error message:

The feature you are trying to use is on a network resource that is unavailable.

Click OK to try again, or enter an alternate path to a folder containing the installation package "iCloud64.msi" in the box below.

I'm not computer savvy, but a search revealed that the file doesn't exist on my computer so how does one fix this?