Safari isn't able to open on my MacBook Pro..

1. Click  in the menu bar and choose “Force Quit”

     or press command +option + esc keys on the keyboard together.

    In the window that opens up, select “Safari”  and click “Force Quit.

2. Relaunch Safari holding the shift key down.

3. If this doesn’t help, use  Malwarebytes for Mac to remove malware.

     https://www.malwarebytes.org/antimalware/mac/

   Download, install , open,  and run it by clicking “Scan” button   to remove adware.

   Once done, quit Malwarebytes Anti-Malware for Mac.

     Install guide:       https://support.malwarebytes.com/docs/DOC-1817

     Uninstall Guide:  https://support.malwarebytes.com/docs/DOC-1190

    The installer may ask you to allow it in System Preferences > Security & Privacy. Allow it.

   Reselect your search engine, reset homepage and disable all extensions and test.

   Reset search engine:    https://support.apple.com/guide/safari/customize-your-search-ibrwe75c2a3c/mac

   Set your Home Page.   https://support.apple.com/guide/safari/set-your-homepage-ibrw1020/mac

Disable or uninstall extensions:

    Section: Manage extensions: https://support.apple.com/guide/safari/use-safari-extensions-sfri32508/mac

I'm glad it is working.

If you are running Yosemite, see if anything here helps. The first link has worked for multiple people. If you remove/replace the file and it doesn’t seem to work, try restarting the computer. I read Apple has released a new version of iTunes that fixes the problem.

https://discussions.apple.com/thread/250021459

https://discussions.apple.com/thread/250025161

https://discussions.apple.com/thread/8573312?page=2

Try setting up another admin user account to see if the same problem continues. Please post back on whether or not this worked. Also try the Safe Mode. Please post back on whether or not this worked.

Isolating an issue by using another user account 

Safe Mode - About

If it works in the Safe Mode, try running this program when booted normally and then copy and paste the output in a reply. The program was created by Etresoft, a frequent contributor.  Please use copy and paste as screen shots can be hard to read. Click “Share Report” button in the toolbar, select “Copy to Clipboard” and then paste into a reply. This will show what is running on your computer. No personal information is shown.

Etrecheck – System Information

If the log won’t post, try posting it in Pastebin and provide a link in a reply        Pastebin