R2026b Prerelease Key Known Issues

MATLAB: Unexpected exit when using specific features

Description: The Prerelease has a bug causing MATLAB to exit when using any of the following features. This will be addressed in R2026b Prerelease Update 1.

• Thread-enabled environments
  • backgroundPool in MATLAB
  • Thread-based pools in Parallel Computing Toolbox
• The variable editor and several Apps
  • MATLAB's variable editor for a sufficiently large tabular variable
  • Classification Learner App in Statistics and Machine Learning Toolbox
  • Time Frequency Analyzer App in Wavelet Toolbox
• Several features across MATLAB and toolboxes:
  • integralInterpolant and AudioReader in MATLAB
  • Background preprocessing in Deep Learning Toolbox
  • freqresp for several models in Control System Toolbox
  • Satellite Scenario Simulation in Satellite Communications Toolbox
  • blockedImageDatastore and Multi-Camera Calibration in Image Processing Toolbox
• Using multiple MCRs in MATLAB Compiler SDK

Workaround: None

ISO Availability

Description: ISO downloads are not currently available for the R2026b Prerelease. We are working to enable this option and will provide an update when they become available. 

Workaround: None

5G Toolbox: Zero throughput when running the example 'Evaluate Performance of Cell-Free mMIMO Networks'

Description: The "Evaluate Performance of Cell-Free mMIMO Networks" example runs but results in zero throughput.

Workaround: None

Simulink Copilot: Product installer is missing Simulink Copilot

Description: Simulink Copilot is not listed as an option in the product installer; therefore, Simulink Copilot features are not available.

Workaround: None

File Exchange: Add-ons not available

Description: File Exchange add-ons cannot be installed from the Add-Ons Panel or Add-On Explorer. Products and support packages are not impacted and will install normally.

Workaround: Download from File Exchange - MATLAB Central and add to MATLAB. When downloading a .mltbx file, double-click to install. For a zip file, extract it, and add it to your path.

For more information on bugs potentially fixed in the prerelease, view the Bug Reports.

Questions?

If you have any questions, please submit a service request or call Technical Support at 508-647-7000.

Content updated: June 17, 2026