WordPress Speed Up Service | WordPress Website Maintenance Packages Reply To: Appearance>Customize doesnt work !!!!, by Mateus Getulio Vieira Are you sure you’re running the 4.9 WordPress version? This is a common error for plugin conflict and old versions problems. Since you haven’t installed any plugin yet this could be the second alternative. Some themes implements functionalities that requires specific features from new WordPress versions, so when you try to run those themes with an old WordPress version that blank page appears. Please let me know if it isn’t the case, so we can continue to look for this problem source. Reply To: Appearance>Customize doesnt work !!!!