There are many reasons for the update error on your antivirus software. Some of them are inadequate storage space, outdated Drivers, or missing files. The Windows update is the first priority in fixing this issue. Hence, it's compulsory to update your Windows to eliminate such errors again.
A troubleshooting tool might help you fix the update error if the main cause wasn't the less storage. The tool is capable of keeping your Windows updated and free from errors. You need to follow certain steps to run this tool.