Manually activating a theme in wordpress, site is not reachable

My wordpress site is not reachable, how can I manually activate a theme? (the current theme h开发者_如何学JAVAas a bug in it, I want to revert to the other theme)

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I would go to the file system to change the theme's directory name or even just delete it. In this case, WP should use its default theme.

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You should go to:

public_html/wordpress/wp-content/themes

And replace its content with the new thime.

(you get there with a FTP client)

Just download a .zip theme (anyone or even better the default one), unzip and upload copying the same structure as the old theme had.

Good luck and be carful, ask if you have doubts before touching anything!