W3total Cache bikin error.

Malam, web saya 89fashions.com kalau diakses normal. tapi ketika masuk di wp-admin muncul pesan seperti berikut:

Fatal error: Uncaught exception 'FileOperationException' with message '<strong>/home/fashion1/public_html/wp-content/w3tc-config/master.php</strong> could not be created, please run following command:<br /><ul><li><strong style="color: #f00;">chmod 777 /home/fashion1/public_html/wp-content/cache/tmp</strong></li><li><strong style="color: #f00;">chmod 777 /home/fashion1/public_html/wp-content/w3tc-config</strong></li>' in /home/fashion1/public_html/wp-content/plugins/w3-total-cache/inc/functions/activation.php:127 Stack trace: #0 /home/fashion1/public_html/wp-content/plugins/w3-total-cache/lib/W3/ConfigWriter.php(159): w3_throw_on_write_error('/home/fashion1/...', Array) #1 /home/fashion1/public_html/wp-content/plugins/w3-total-cache/lib/W3/Config.php(71): W3_ConfigWriter->save() #2 /home/fashion1/public_html/wp-content/plugins/w3-total-cache/lib/W3/CloudFlare.php(174): W3_Config->save() #3 /home/fashion1/public_html/wp-content/plugins/w3-total-cache/lib/W3/Plugin/CloudFlare.php(52): W3_CloudFlare->update_ip_ranges() #4 /h in /home/fashion1/public_html/wp-content/plugins/w3-total-cache/inc/functions/activation.php on line 127

masalah ada pada w3total-cache. bagaimana cara mengatasinya?