My desktop computer (Dell XPS 8700, running Windows 10 Pro 64 bit, version 1709, using Avast Premier AV) just finished installing the Tuesday night update (including cumulative update KB4103727 but NOT the April features update to version 1803, which has not yet come my way). I then got a notification from Avast that it had detected a "threat" named SearchProtocolHost.exe in the sysWOW64 folder. I sent it to the virus chest.
Then I looked up SearchProtocolHost.exe and found it is a normal part of Windows 10, at least when found in the system32 folder. So I went back and looked. In the system32 folder is a copy of SearchProtocolHost.exe along with a number of other apparently related files. In the sysWOW64 folder all those other search-protocol related files are present, but the SearchProtocolHost.exe has been removed (to the Avast Virus Chest).
Question arising, is this a mistake, and should I restore the file to the sysWOW64 folder?
Further question (department of idle curiosity): if that copy does belong in sysWOW64, and I neglected to restore it, would it be restored anyway in the next Windows Cumulative Update?
I suppose it quite possible that the 32 bit and the 64 bit versions of this file could be different. I dimly remember that back in the heroic days we had a little utility that would compare two files, byte by byte, and tell you whether or not they were identical (and if not, what was different). Is anything like that still around?
I know that's ancient history. From those long-ago pre-Photoshop days, I also remember byte-editing photo images, pixel by pixel. Not nearly as hard as you might think, because you quickly develop an eye for patterns across a page of hex notation. Easy to fix small blemishes that way. For the rest, I prefer Photoshop (or IrfanView <G>).