You say you saved the file to disk. What kind of disk? Have you copied it over to to the hard drive on your new computer? Have you gone ahead and opened the file? You could try opening it and then saving it in a new location.
I have heard of this happening before and recall it has something to do with the way the Windows file manager works.
A quick search revealed this:
"To see the issue, you need to have the Preview pane open (which is turned off by default - which is a good thing - on Win 7, Win 8 and Win 10), Windows Explorer needs to be set to a thumbnail view, the model needs to have a thumbnail and the user needs to double click on the model to open it. Therefore, please make sure the preview plane is unchecked or closed..."
Set Windows Explorer to use a non-thumbnail view.
If you open the file once, close it and then double click on it again to open it, it will open fine. Or open it from File>Open.