If you are having issues with installation, start by disabling spam/virus protection software and local firewalls until after the installation. Also, try running the installer by right-clicking on the installer executable file and choose "Run as administrator". It may be necessary to log into your computer with an administrative account before installing software. If you are having issues updating your software from within Altium Designer, try running the online installer from here: https://www.altium.com/products/downloads Sometimes firewalls or routers blocking some of the installation traffic or other factors cause the online installer to fail. This Knowledge Base article describes how to acquire the offline installer package, which is like having the installer on a set of floppy discs in a zipped file: https://www.altium.com/documentation/knowledge-base/altium-designer/offline-installer You may get some insight into the root cause of the issue by checking the Installation and other log files which can be found in C:\Users\Public\Documents\Altium\Logs. There might be something helpful in the Windows Event Viewer. Regarding these two errors: System Error. Code: 5. Access denied
System Error. Code: 2. The system cannot find the file specified (usually in your Temp directory)
We get a handful of similar cases after a new release. This is most likely caused by virus protection software such as Windows Defender. Please turn off your virus/malware protection software before attempting the installation. Many customers have said that when they tried again later in the week, after an anti-virus software update, the installer was able to finish without error and Altium Designer is working for them. Sometimes re-booting is necessary for the virus scanning software to complete its update. If updating virus protection doesn't happen or doesn't help, try adding the Altium Designer installer to the exclusion list for the Anti-virus software. Uninstalling any partial install, re-booting, turning off your virus protection software (or at least updating the software to a newer version or adding the exclusion), then trying the installer again usually will resolve this issue. Using the offline installer may be helpful in this situation. (See the third paragraph at the top of this article.) As a fallback option, your virus protection probably already knows about older versions of Altium Designer, so if this is holding you up, you can install a previous version. If you have IT support, show them the system error code 2 message that indicates the file in the Temp folder can't be found. Also send them these suggestions. They should be able to go out and get an update to be installed, or add the exclusion, or they can turn off virus protection for you for the purpose of running the installer then turn it back on again. If you have issues uninstalling, it is probably because the installation didn't finish properly. Here's our Knowledge Base article on uninstalling: https://www.altium.com/documentation/knowledge-base/altium-designer/how-to-perform-a-thorough-uninstall
Regarding the error "Cannot patch": Cannot patch...
This issue is usually resolved by using the offline installer. (See the third paragraph at the top of this article.)