We apologize for the delay in replying to this.
Are you still getting this message ? If yes, I suggest you to update your DAT files first and try to download the installer again.
If you continue getting this message after updating the DATs, would be good to check the the "Scan Time" and "Scan Items" in your AV settings by clicking on the OnDemand Scan Properties.
It also suggests that system is either crawling for some reason (other things are getting CPU time), or something else on the system is hindering the scanner being able to obtain some simple information about the file in question.
Anyway, this message does not indicate a software malfunction, properly, but the amount of time taken to scan the file depends primarily on the following factors:
* File complexity
* File size
* File location
* File type. File extensions such as .jar, .chm, .cab, and .zip are all archive files that typically use a very high compression. To scan these archives, each file must be extracted from the archive. This can use a large amount of memory depending on the type of data in the archive and how well it compresses.
* Processing power of the computer scanning the files (and amount of memory if the file must be uncompressed)
* Network speed (if the file has to be copied over a network to be scanned)
Please see more details at: https://kc.mcafee.com/corporate/index?page=content&id=KB55869
Hope this helps !