Dear MathWorks Support Team,
I am reporting a cross-platform internal error in MATLAB R2025b involving the interaction between the Search Path and Dropbox. This issue has been consistently reproduced on both Windows 11 and macOS (Sequoia).
The error occurs whenever a Dropbox-synced folder is added to the MATLAB Search Path. After running any script from that path, MATLAB throws a std::exception: "Unexpected mxArray type returned from feval. Expected class std::basic_string… but found string." originating from internal.matlab.datatoolsservices.WSBUtil.getWorkspaceDisplay.
I have already performed the following troubleshooting steps to isolate the issue:
Clean Reinstallation: Performed a complete uninstall and deleted all MathWorks-related metadata folders, including %AppData%MathWorks, %LocalAppData%MathWorks, and the MATLAB folder in Documents.
Configuration Reset: Reset the userpath and cleared all pathdef.m files to ensure no legacy settings from previous versions (like R2024b) were interfering.
Cross-Platform Testing: Confirmed the exact same behavior on a newly purchased MacBook and a Windows PC.
Path Isolation: Confirmed that the error only occurs when the Dropbox folder is added to the "Set Path" list. It does not occur if the directory is accessed only via the cd command.
GUI Minimization: Even after closing the Workspace and Current Folder browsers and disabling datatips, the internal WSBUtil error still triggers upon script completion.
It appears the R2025b engine incorrectly handles path metadata from cloud-synced file systems, passing a string object where internal C++ UI functions expect a char array. Given that my research workflow across multiple machines relies entirely on Dropbox, this bug is a significant hindrance.
I look forward to your technical analysis and a potential patch for this engine bug.
Best regards,Dear MathWorks Support Team,
I am reporting a cross-platform internal error in MATLAB R2025b involving the interaction between the Search Path and Dropbox. This issue has been consistently reproduced on both Windows 11 and macOS (Sequoia).
The error occurs whenever a Dropbox-synced folder is added to the MATLAB Search Path. After running any script from that path, MATLAB throws a std::exception: "Unexpected mxArray type returned from feval. Expected class std::basic_string… but found string." originating from internal.matlab.datatoolsservices.WSBUtil.getWorkspaceDisplay.
I have already performed the following troubleshooting steps to isolate the issue:
Clean Reinstallation: Performed a complete uninstall and deleted all MathWorks-related metadata folders, including %AppData%MathWorks, %LocalAppData%MathWorks, and the MATLAB folder in Documents.
Configuration Reset: Reset the userpath and cleared all pathdef.m files to ensure no legacy settings from previous versions (like R2024b) were interfering.
Cross-Platform Testing: Confirmed the exact same behavior on a newly purchased MacBook and a Windows PC.
Path Isolation: Confirmed that the error only occurs when the Dropbox folder is added to the "Set Path" list. It does not occur if the directory is accessed only via the cd command.
GUI Minimization: Even after closing the Workspace and Current Folder browsers and disabling datatips, the internal WSBUtil error still triggers upon script completion.
It appears the R2025b engine incorrectly handles path metadata from cloud-synced file systems, passing a string object where internal C++ UI functions expect a char array. Given that my research workflow across multiple machines relies entirely on Dropbox, this bug is a significant hindrance.
I look forward to your technical analysis and a potential patch for this engine bug.
Best regards, Dear MathWorks Support Team,
I am reporting a cross-platform internal error in MATLAB R2025b involving the interaction between the Search Path and Dropbox. This issue has been consistently reproduced on both Windows 11 and macOS (Sequoia).
The error occurs whenever a Dropbox-synced folder is added to the MATLAB Search Path. After running any script from that path, MATLAB throws a std::exception: "Unexpected mxArray type returned from feval. Expected class std::basic_string… but found string." originating from internal.matlab.datatoolsservices.WSBUtil.getWorkspaceDisplay.
I have already performed the following troubleshooting steps to isolate the issue:
Clean Reinstallation: Performed a complete uninstall and deleted all MathWorks-related metadata folders, including %AppData%MathWorks, %LocalAppData%MathWorks, and the MATLAB folder in Documents.
Configuration Reset: Reset the userpath and cleared all pathdef.m files to ensure no legacy settings from previous versions (like R2024b) were interfering.
Cross-Platform Testing: Confirmed the exact same behavior on a newly purchased MacBook and a Windows PC.
Path Isolation: Confirmed that the error only occurs when the Dropbox folder is added to the "Set Path" list. It does not occur if the directory is accessed only via the cd command.
GUI Minimization: Even after closing the Workspace and Current Folder browsers and disabling datatips, the internal WSBUtil error still triggers upon script completion.
It appears the R2025b engine incorrectly handles path metadata from cloud-synced file systems, passing a string object where internal C++ UI functions expect a char array. Given that my research workflow across multiple machines relies entirely on Dropbox, this bug is a significant hindrance.
I look forward to your technical analysis and a potential patch for this engine bug.
Best regards, r2025b internal engine bug, std::exception, unexpe, dropbox integration, search path conflict, cloud-s MATLAB Answers — New Questions

​