doxgyen failing to install on Appveyor

We have had many problems installing chocolately packages on Appveyor, causing us to downgrade installation failures to just warnings we continue past. We noticed recently that doxygen has been failing to install every time:

https://ci.appveyor.com/project/DynamoRIO/dynamorio/builds/29690836?fullLog=true

choco install --timeout 600 -y doxygen.portable imagemagick.tool ghostscript || true
Chocolatey v0.10.8
Installing the following packages:
doxygen.portable;imagemagick.tool;ghostscript
By installing you accept licenses for the packages.
Progress: Downloading doxygen.portable 1.8.11... 100%

doxygen.portable v1.8.11 [Approved] - Likely broken for FOSS users (due to download location changes)
doxygen.portable package files install completed. Performing other installation steps.
Attempt to get headers for http://ftp.stack.nl/pub/users/dimitri/doxygen-1.8.11.windows.x64.bin.zip failed.
  The remote file either doesn't exist, is unauthorized, or is forbidden for url 'http://ftp.stack.nl/pub/users/dimitri/doxygen-1.8.11.windows.x64.bin.zip'. Exception calling "GetResponse" with "0" argument(s): "The remote name could not be resolved: 'ftp.stack.nl'"
Downloading doxygen.portable 64 bit
  from 'http://ftp.stack.nl/pub/users/dimitri/doxygen-1.8.11.windows.x64.bin.zip'
ERROR: The remote file either doesn't exist, is unauthorized, or is forbidden for url 'http://ftp.stack.nl/pub/users/dimitri/doxygen-1.8.11.windows.x64.bin.zip'. Exception calling "GetResponse" with "0" argument(s): "The remote name could not be resolved: 'ftp.stack.nl'" 
This package is likely not broken for licensed users - see https://chocolatey.org/docs/features-private-cdn.
The install of doxygen.portable was NOT successful.
Error while running 'C:\ProgramData\chocolatey\lib\doxygen.portable\tools\chocolateyInstall.ps1'.
 See log for details.

We could try the doxygen package instead of doxygen.portable.