HI there Alia80,
It sounds like you are setting your Finder Preferences to open to a specific folder when you open a new window but it seems to keep reverting to what it was previously set to. I would first boot to Safe Mode and so some system level caches can be cleared, and a disk verification and repair gets done automatically:
Try safe mode if your Mac doesn‘t finish starting up
Follow these steps to start up into safe mode.
- Start or restart your Mac.
- Immediately after you hear the startup sound, press and hold the Shift key.
- Release the Shift key when you see the Apple logo appear on the screen.
After the Apple logo appears, it might take longer than usual to reach the login screen or your desktop. This is because your Mac performs a directory check of your startup disk as part of safe mode.
To leave safe mode, restart your computer without pressing any keys during startup.
Once you log into safe mode leave it by doing a regular restart and test the issue again.
If it persists after that test this out in a new admin user on your computerand let me know what happens there:
OS X El Capitan: Set up users on your Mac
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