why is my dash board blank
Are you using Safari as your web browser? I have heard of that happening occasionally with Safari and I suggest you use either Google Chrome or Firefox as your web browser when using Canvas. To double check that you are enrolled in active classes on Canvas, try clicking the Courses button on the left side of Canvas and then All Courses. If you don't see courses listed here, or if the ones you see all say unpublished next to them, that could also explain it.
When you say it's blank, is it showing you have no enrollments? Or is the entire page itself blank where you can't see any content at all on the entire screen? If it's the former, you may not be able to view your courses before they begin. If it's the latter, try Rick's suggestion as it's usually an error within the browser itself. Make sure you're also using the latest version of the browser.
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