Problem: Custom agent icons for Windows endpoints are not updating even via the Agent-->Upgrade Version-->Update Agent-->Force update option.
Cause: The icons exceed the maximum depth of 256 (or 8 bit) colors or 32 x 32 pixel dimensions.
Resolution: Use the correct color depth for the Windows endpoint agent icons.
Check for the color depth and dimensions by downloading a .zip file of all the icons being used and check their file properties via right-click-->Properties-->Details. If either the colors or dimensions are greater than 256 colors (or greater than 8 bits) and 32 x 32 pixels, then the custom icon deployment will fail.