PTO is cloud-based and not OS dependent.  I suppose you're able to reach the website but all you see is a spinning circle, spinning dots, or a blank space.  This is a known performance issue and Intuit is still working on a permanent fix.

In the meantime, you should use one or a combination of the following and that will always solve your problem:

• Use an incognito window
• Reload frame
• Clear cookies/cache/history
• Use another browser/computer/device
• Restart browser/computer/device