[Win x64] R installation & Registry

[myso42]

I just want to share experience for people who may struggle figuring out which entry in the registry is actually used to select the R install.

My experience is that R entries in windows registry are quite messy and I spent a bit of time figuring out exactly WHICH entry in the registry is used to find R by the type provider.

In my registry (win64), I can find paths to R install in :

HKEY_LOCAL_MACHINE\Software\R-core\R\InstallPath
HKEY_LOCAL_MACHINE\Software\R-core\R[version]\InstallPath
HKEY_LOCAL_MACHINE\Software\R-core\R64\InstallPath
HKEY_LOCAL_MACHINE\Software\R-core\R64[version]\InstallPath
HKEY_LOCAL_MACHINE\Software\Wow6432Node\R-core\R\InstallPath
HKEY_LOCAL_MACHINE\Software\Wow6432Node\R-core\R[version]\InstallPath
HKEY_LOCAL_MACHINE\Software\Wow6432Node\R-core\R32\InstallPath
HKEY_LOCAL_MACHINE\Software\Wow6432Node\R-core\R32[version]\InstallPath

In Visual Studio and for x86 process, the key actually used, on my machine, is
HKEY_LOCAL_MACHINE\Software\Wow6432Node\R-core\R\InstallPath

For a x64 process, it is :
HKEY_LOCAL_MACHINE\Software\R-core\R64\InstallPath

The InstallPath under [version] does not seem be used.

Hope this may help someone.

[sergey-tihon]

According to the R documentation,

When you run the R installer, there are options (under ‘Select Additional Tasks’) to ‘Save version number in registry’ and (for Administrator installs) ‘Associate R with .RData files’.

If you tick the first option, the following string entries are added to the Windows registry:

• HKEY_LOCAL_MACHINE\Software\R-core\R\Current Version contains the version number, currently 3.0.2.
• HKEY_LOCAL_MACHINE\Software\R-core\R[version]\InstallPath (where [version] is currently 3.0.2) contains the path to the R home directory.
  If you do not have administrative privileges on the machine while running the installer, then the entries are created under HKEY_CURRENT_USER. The same entries are also created under Software\R-core\R32 or Software\R-core\R64, for 32- and 64-bit R respectively.

I think that we can identify R location relying on the described registry structure.

P.S. On my machine I see the following registry structure:

[hmansell]

Do you believe the RProvider code is not currently identifying the code
according to those rules?

On Tue, Oct 1, 2013 at 1:33 AM, Sergey Tihon notifications@github.comwrote:

According to the R documentationhttp://cran.r-project.org/bin/windows/base/rw-FAQ.html#Does-R-use-the-Registry_003f
,

When you run the R installer, there are options (under ‘Select Additional
Tasks’) to ‘Save version number in registry’ and (for Administrator
installs) ‘Associate R with .RData files’.

If you tick the first option, the following string entries are added to
the Windows registry:

• HKEY_LOCAL_MACHINE\Software\R-core\R\Current Version contains the
  version number, currently 3.0.2.

• HKEY_LOCAL_MACHINE\Software\R-core\R[version]\InstallPath (where
  [version] is currently 3.0.2) contains the path to the R home directory. If
  you do not have administrative privileges on the machine while running the
  installer, then the entries are created under HKEY_CURRENT_USER. The same
  entries are also created under Software\R-core\R32 or Software\R-core\R64,
  for 32- and 64-bit R respectively.

  I think that we can identify R location relying on the described
  registry structure.

—
Reply to this email directly or view it on GitHubhttps://github.com//issues/28#issuecomment-25426504
.

[sergey-tihon]

I see no mention about top level InstallPath in docs. Do you sure that it must be in registry?

[hmansell]

It always has been when I have done an install.