Why do I get a warning "Name is nonexistent or not a directory" about the Editor_vxdxq folder?

After installing R2020a PreRelease I get the following warning in the MATLAB Command Window on startup:

Warning: Name is nonexistent or not a directory:
C:\Users\<my username>\AppData\Local\Temp\Editor_vxdxq

Additional notes:

1) This warning does not appear in MATLAB R2019a.

2) Furthermore, when I navigate to "C:\Users\username\AppData\Local\Temp\" I do not see the "Editor_vxdxq" folder when MATLAB R2020a is closed (or when R2019a is open). This file appears as soon as R2020a is open.

Answer 1

[MathWorks Support Team]

The warning that you are seeing, as well as the automatic generation of the Editor_vxdxq folder is an expected behavior. Essentially, this folder gets automatically created in the background by the Live Editor in MATLAB. When we open MATLAB R2020a this file gets created, if we call the "savepath" command after this, the folder will be saved to the path but it might not exist in the future when the path is reloaded again (hence you see the warning). That being said, there is no concern with the warning itself as the generation of this folder is handled by MATLAB. We have two options to resolve the warning:

1) Remove the "Editor_vxdxq" folder from the path and save it:

• Open MATLAB
• Enter the following command in the MATLAB Command Window:

>> pathtool

• Use the Set Path dialog box to remove Editor_vxdxq folder from the path and click "Save"
• On the MATLAB Command Window, enter

>> savepath

After this you should not get the warning, and can ignore the generation of this file. Since this folder was meant to be temporary, removing it from the MATLAB path should not result in any unexpected side effects in the current MATLAB session. Should you need to save the search path again in the future, make sure to remove the temporary directory again if it appears before saving.

2) You can manually turn the warning off with the following command:

>> warning('off', 'MATLAB:mpath:nameNonexistentOrNotADirectory')

One thing to note is that we generally recommend against using the "savepath" command (unless advised by the MathWorks staff as part of a troubleshooting step) as it can have some serious consequences if an unintended file gets added to the path. To add additional items to the path, we recommend to instead use the "addpath()" command in the "startup.m" file. For more information, please see the following link:

https://www.mathworks.com/help/matlab/ref/startup.html

[Walter Roberson]

I believe that the path item is required for live editor to be able to process one section at a time. There is no actual internal mechanism for executing starting and ending at particular locations: instead the matlab code for the section is copied to a temporary file and the file run as a script.

[Image Analyst]

Amir, the permanent solution is to put

warning('off', 'MATLAB:mpath:nameNonexistentOrNotADirectory');

into your startup.m file.

>> edit startup.m

Then add that line of code and save it.

[Walter Roberson]

Yes. C:\Users\<user name>\AppData\Local\Temp\Editor_ followed by 5 letters is Live Script stuff.