Deselect any language localization files you don’t need (saves ~10 MB of disk space).
Click the Customize button in the bottom-left corner. Ensure the following components are checked:
| QuickTime Version | Compatible Mac OS | Status for 10.5.8 | | --- | --- | --- | | QuickTime 7.7+ | OS X 10.6 Snow Leopard & Later | – Will crash on launch | | QuickTime 7.6.x | OS X 10.5.8 (Partial support) | Unstable – Codec conflicts | | QuickTime 7.5.5 | Mac OS X 10.5.5 – 10.5.8 | Optimal – Full codec suite | | QuickTime 7.4.5 | OS X 10.4 Tiger / Early Leopard | Missing – H.264 improvements |
This is normal. QuickTime 7.5.5’s YouTube browser plugin relies on an API that Google deprecated in 2015. Use TenFourFox (PowerPC) or Roccat (Intel) browsers for web video.
Try this direct link to Apple’s servers (copy and paste into your browser):