Try disabling your virus/malware software temporarily to see if it makes a difference. Your virus &/or Malware scanning software may be scanning every file as it is loaded. A warm reboot will not guarantee that the physical RAM has been completely cleared. This is especially true for computers left on for several days. Memory leakages from various applications will consume the physical RAM over time.

This documentation has more detail (and images): If you see a yellow, orange, or red square at the bottom right of your screen (just to the left of the panels button, your Windows system resources usage is getting high. Your system might not meet the recommended System Requirements (especially for Processor, RAM, and Graphics card):

Solution Details If you are running a 64-bit operating system, you may notice better performance with the current version of Altium Designer which is 64-bit software that can take advantage of today's modern computing hardware like all of your RAM and features such as multi-threading. Here is a long list of things that may help you track down an underlying cause.

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