[R] Error msg trying to load R Commander with an older R edition...

[John Fox]

Dear Brian,

On 2021-09-13 9:33 a.m., Brian Lunergan wrote:
> Hi folks:
> 
> I'm running Linux Mint 19.3 on my machine. Tried to install a more
> recent edition of R but I couldn't seem to get it working so I pulled it
> off and went with a good, basic install of the edition available through
> the software manager. So... I'm running version 3.4.4.
> 
> Mucking about with the attempt at a newer edition seems to have left
> some excess baggage behind. When I loaded R Commander and attempted to
> run it I received the following error message.
> 
> Error: package or namespace load failed for ‘car’ in readRDS(pfile):
>   cannot read workspace version 3 written by R 3.6.2; need R 3.5.0 or newer
> During startup - Warning message:
> package ‘Rcmdr’ in options("defaultPackages") was not found
> 
> I get a similar message in Rkward when I try to load any more packages.
> 
> Is there any solution for this? Any "leftovers" I can track down and
> delete? Any assistance would be greatly appreciated.

It's hard to know exactly how many things are wrong here, but one 
problem seems to be that you saved the R workspace in the newer version 
of R, and that the older version is trying to load the saved workspace, 
which is an incompatible format.

The workspace is probably saved in the file .RData in your R home 
directory. If that's the case, then you should see a message to this 
effect when R starts up. I'd begin by simply deleting this file.

Then, if the Rcmdr package fails to load with an error indicating that 
car or another package is missing, I'd try installing the missing 
package(s).

Finally, you might be better off persevering in your attempt to install 
the current version of R rather than the quite old version that you're 
trying get working.

I hope this helps,
  John

> 
> Kind regards...
> 
> 
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