NO EFFECTS AFTER STARTS

FAQ: How to reset (trash) preferences in After Effects?

Here is how you can reset the preferences:

Press Alt (Windows) or Option (Mac OS) while launching After Effects. You can release the Alt or Option key when the splash screen appears.

To reset preferences and plug-in cache at the same time, hold down Control-Shift-Alt (Windows) or Command-Shift-Option (Mac OS) while the application is starting. Release the keys when the splash screen appears.

Without any system information we can't really tell you much. Start by deleting the preferences file and consider reinstalling AE with sufficient user privileges. Anything more will require proper details.

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