In your order history, I see that you had purchased eCart 4 as well, did you have eCart 4 installed before installing eCart 5.
If so, did you remove eCart 4 from the extension manager first, or did you install eCart 5 over eCart 4?
If you installed eCart 5 over eCart 4, your configuration folder is most likely corrupted, follow step 2 at the following link:
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