Freshly (re)installed MatLab R2021A error message upon startup

My newly (re) installed matlab R2021A drops this error message whenever I start it, and plot commands do not work. Can someone help me how to resolve?

Many thanks!

Warning: The following error was caught while executing 'internal.hotplug.EventSource' class destructor:

Dot indexing is not supported for variables of this type.

Error in internal.hotplug.EventSource/stop (line 74)

obj.Channel.close();

Error in internal.hotplug.EventSource/delete (line 57)

stop(obj);

Error in internal.hotplug.EventSource (line 37)

internal.hotplug.EventSource.lock();

Error in internal.deviceplugindetection.Manager (line 173)

obj.USBDetectorObject = internal.hotplug.EventSource();

Error in internal.deviceplugindetection.Manager.getInstance (line 246)

devicePluginManagerInstance = internal.deviceplugindetection.Manager();

> In internal.hotplug.EventSource (line 37)

In internal.deviceplugindetection.Manager (line 173)

In internal.deviceplugindetection/Manager/getInstance (line 246)

Error: File: class.m Line: 1 Column: 1

At least one END is missing. The statement beginning here does not have

a matching end.

Error in setdiff>setdiffR2012a (line 189)

if ~strcmpi(class(a),class(b))

Error in setdiff (line 111)

[varargout{1:nlhs}] = setdiffR2012a(varargin{:});

Error in matlab.lang.makeUniqueStrings (line 108)

stringsToProtect =

inStr(setdiff(1:numel(inStr),exclStrOrElemToChk));

Error in matlab.internal.json.makeStructure (line 42)

names = matlab.lang.makeUniqueStrings(names, 1:numel(names),

namelengthmax);

Error in matlab.visualize.task.internal.utils.getJSONMetadataFromFiles

Error in

matlab.visualize.task.internal.utils.FunctionMetaData.updateMetaData

Answer 1

[Yongjian Feng]

From matlab command line window, type

which class.m

The error complains about class.m

[Peter Varkonyi]

Thank you for your help! I understand now that there was a file class.m in my computer that caused a conflict with the built-in file with the same name. After removing this file, the problem is resolved!