Hi Vimdhayak,
It is my understanding that you are facing an error in installing Simulink and other tools on MATLAB. This error is usually caused by 2 things:
1. Lack of Administrative Privileges
If you do not have administrative privileges on the computer you are trying to install MATLAB/add-ons on, you will either need to pick a different directory or ask your computer's administrative for privileges to install the software.
2. Antivirus and Security Software
It is also possible that security software (such as antivirus software) blocked the MathWorks Product Installer from accessing areas of your computer which are required for installation. The installation log in your temp folder will usually indicate the name of the program that caused the problem.
To resolve this issue, temporarily disable your security software while installing MathWorks products. You may require your system administrator's assistance to disable your security software.
Hope this helps!
