I came here in search with the same problem.
in Windows 8.1, the date in ISO 8601 format (YYYY-MM-DDThh:mm:ss) didn't work for me if I added Thh:mm:ss to the date. Date without time was ok. '2014-1-15'
But this did work with time: 15-Jan-14 16:24
You might need to use your regional format e.g. 01/15/14 4:24pm or universal: 2014-1-15 16:24
Instead of searching for the modification time, I would suggest you to look for files CREATED on that date and time. As files has created/modified/accessed dates:
It's also working without "System." for me:
Also, in our case, it's good idea to make your search broader, like 10 minutes period:
DateCreated:15-Jan-14 16:24..15-Jan-14 16:34
or with date in language independent format:
DateCreated:2014-1-15 16:24..2014-1-15 16:34
you are entering this string in the File Explorer window in root directory on your main drive (c:) to a Search This PC combo box right of the address text box.
Also you need to include System Files in search because I think AppData folder is outside indexed space and will not be searched otherwise. And that's where viruses like to reside.
To do this click on Search in Menu, then Advanced Options and System Files ON
In the result pane, you'll see MODIFICATION dates, some out of range you specified. If you will look at the property of each file, you'll see creation date is in specified range. They have been modified after they were created
(I made a picture but can't post it)