Cannot open old operational simulink program

I cannot open old working simulink programs (2018) with 2021a. It said "Error using open (line 143) File 'C:\......slx' does not contain a valid Simulink model in SLX format: Content types stream does not exist". I also cannot open old working .m file instead of a small square.

[Walter Roberson]

Is it possible for you to attach the slx for testing?

[John D'Errico]

If you cannot open the old m-file also, this makes it likely something is corrupt, as an m-file is just a text file.

Can you open the problematic m-file with some other text editor?

Answer 1

[Suraj Kumar]

Hi @Yong Zhou,

I understand the issue that you are facing.The error could arise for various reasons.

Here are a few workarounds that you can try :

1. Execute the following commands in MATLAB Command Window:

restoredefaultpath
rehash toolboxcache
savepath 

2. Check the location of the temp directory after typing the 'tempdir' command on your MATLAB command prompt:

tempdir

Ensure the path of the temp directory you get after typing the command is local on your machine.And clean your temp directory if it is full and then try to run your model.

3.Performing a clean reinstalling of MATLAB might also help.You can refer to the following link for the steps to re-install:

https://www.mathworks.com/matlabcentral/answers/131519-how-do-i-perform-a-clean-installation-of-matlab

Hope this helps!