Skip to main content

Sessions Fail to Start in Workbench with R 4.5.1

Gbenuola Thontteh
  • Updated

Issue

After upgrading to R 4.5.1 on Posit Workbench 2024.04 or earlier, sessions fail to start with an error containing 'undefined symbol: Rf_countContexts' and exit code 127.

Description

This is a known compatibility issue between R 4.5.1 and older versions of Posit Workbench. The issue manifests when attempting to start new RStudio IDE sessions, while other IDEs like Jupyter and VS Code may continue to work normally.

Solution

There are two ways to resolve this issue:

Option 1: Downgrade R Version

  1. Install R 4.4.0 on your system.
  2. Modify your rserver.conf to make sure rsession-which-r points to R 4.4.0.

Option 2: Upgrade Workbench

  1. Upgrade to Posit Workbench 2025.05.2 or later, which includes full compatibility with R 4.5.1.
  2. Follow the standard upgrade procedures for your installation.

If you're still having issues, you can reach out to Support by opening a ticket here.

Related articles