We have been receiving reports recently of failed installations on both Mac and Windows. If you have the same problem, please:
- Check once more all the instructions at http://www.gcdkit.org/download
- In particular, make sure that you install R first, in appropriate version (that is 3.6.0 for GCDkit 6.0)
- If you are behind a proxy, select Internet2 option during Custom R installation
- Check that you are online before installing the supporting libraries
- For installation, run R with admin privileges
- If you receive a message saying that RODBC is not available for R 3.6.0:
 Download the zipped version of the RODBC library from https://cran.r-project.org/bin/windows/contrib/3.6/RODBC_1.3-16.zip.
 Go to RGUI menu Packages>Install package(s) from local zip files... and browse for this downloaded file on your disc. DO NOT unzip it beforehand.
- In case you are missing any other R libraries, their appropriate zipped version can be found at https://cran.r-project.org/bin/windows/contrib/3.6/, downloaded and installed analogously to the case of RODBC.
I am pleased to announce that we are just finishing a GCDkit version 6.1 that should fix a few known bugs and feature, among other things, also offline installer.