[SOLVED] Trouble unzipping cygiconv-2.dll on Windows 7 (0.8.5)

Trying to update from Xonotic 0.8.2 to 0.8.5 on my Windows 7 desktop. I've downloaded xonotic-0.8.5.zip, but when I try to unzip it, file cygiconv-2.dll fails with error code 0x80004005. 

All other files appear to be unzipped normally, but if I try running update-to-release.bat, rsync.exe fails with system error "cygiconv-2.dll missing".

I'm thinking of trying to download Cygwin and copy the DLL from that package. Any other ideas?

I tried copying the DLL from Cygwin and running update-to-release.bat generates a new error: rsync.exe application error "Cannot correctly run application (0xc000007b)". Any idea?

Replacing rsync.exe that came zipped with 0.8.5 with the latest rsync.exe version from MinGW allowed update-to-release.bat to run to normal completiong.

I get a similar error (transcribed below) while unzipping the full xonotic-0.8.5.zip file in Windows 10, also complaining about cygiconv-2.dll.  I also tried using a Linux computer (namely, LMDE=Linux Mint Debian Edition 5), and it successfully unzipped all files.  Using LMDE's own zip facility, I unzipped and then re-zipped the contents of xonotic-0.8.5.zip.  My own zip file unzips in Windows without any trouble, including cygiconv-2.dll.  I think something went wrong in the process of zipping cygiconv-2.dll into the xonotic-0.8.5.zip provided on this website.

1 Interrupted Action
An unexpected error is keeping you from copying the fie.  if you continue
to receive this error, you can use the error code to search for help with this
problem.
Error:  0x80004005:  Unspecified error
  cygiconv-2.dll
  Type: Application extension
  Date modified:  2022-06-27 8:32 PM
  Size: 0.98 MB
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