Sapphire Lake

[FOOOOORE!]

Has anyone besides me had trouble decompressing this file? I normally use WinRAR, which gives a checksum error when I use it on this archive (strangely it extracts the Readme text file no problem, but not the .crz). I was advised to use Windows Explorer instead, but I get the same problem. When I look at the .zip file with a hex editor (and also another one I created with Explorer), I see the first two bytes are "PK", so it appears Windows is just using the free PKZIP source provided by Phil Katz (1962-2000, interesting story there). So this should be handled easily by WinRAR, as I have done with every other course downloaded from this site.

[pmgolf]

My SaphireLake.zip opened fine with Winrar 5.8 and also Winzip 8.1 (I prefer the old, free versions). I suggest you re-download the file - I suspect it didn't finish downloading properly.

Pete

[FOOOOORE!]

Thanks for the feedback. I did DL it twice with no difference, but I'll give it another try today. It does look as though Windows is just using the freely available PKZIP code, so there should be no difference there between Explorer and WinZIP, and WinRAR uses the same source (as they all do, the LZW algorithm has been around for many years now).

[FOOOOORE!]

I finally tracked the problem down to what I download files with: IDM (or Internet Download Manager). I don't know about most people, but I don't use many of the utilities that come with Windows. Who actually relies on Defender, for example, to protect their PC from viruses? Or how about Explorer, instead of Chrome, Firefox, Opera, or Anything Except Explorer? IDM has successfully DL'd many, many files for me, but was at fault in this particular case. I DL'd the file with IDM and also just using Windows (Chrome is my browser). Although the two files are exactly the same size, a hex editor calculated different checksums for the two files and it appears that about halfway through the file, IDM screws up. So, a good learning experience; I know what to do next time it happens, which luckily is a very rare occurrence.