I can no longer get my pen tool, rectangle tool, and other tools to snap to existing points, joining at the point. Instead, I have to guess the placement and it doesn't make it exact and leaves messy linework.
How can I change this setting so my tools snap to existing points and lines?
What are you snap settings? You can snap to point. Also having Smart Guides on is helpful. There are many to pick from that can help for other things:
Glad it is working.
Are Smart Guides on, and are both Snap To Grid and Pixel Preview off?
If either is on, Smart Guides will fail to guide you, however smart they are.