Re: TikiWiki 6 and PHP compatiblity
I only did an svn install of Tiki 6 (6.15) on a system with PHP 5.5 to try and recreate your problem.
Are you sure GD Graphics Library is installed on the new server? Go to Admin -> phpinfo and check the "GD Support" (hopefully it says enabled) and "GD Version".
GD dynamically generates the thumbnails from the original image (not like the old Image Gallery where a separate thumbnail was generated and kept). If GD is not available, that would cause the problem you are having.
Tom
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