After activating a child theme (that seemed to be incorrectly developed), it first generated an error screen and then the entire site (front-end and back-end) shows white screen. WordPress community has referred this to White Screen of Death. The quick fix to this issue: 1) FTP/SSH to the wp-content/themes directly. 2) Rename the folder of the themes you last selected causing the White Screen of Death 3) Re-login to WordPress site wp-admin 4) Go to Appearance menu and re-activate the last working theme
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