If one of your servers is failing the screenshot test showing the Windows Device Ready booting screen, this means that the Datto needs to wait longer for the server to be completely booted before it takes the screenshot verification. 

To resolve this, follow these instructions:

1. Over the Datto web portal, click on the Protect tab.
2. Scroll down and find the server that has the screenshot failure.
3. Click on Configure Agent Settings on the left.
4. Scroll down to the section Screenshot Verification.
5. .Increase the Additional wait time to double the value that it has currently.
6. Hit Apply to complete.
7. Then to start a manual screenshot test, go back to the Protect tab.
8. Find the server on the list.
9. Click on the Manage Recovery Points option.
10. Choose the latest recovery point available and then click on the Screenshot Verification column.
11. After this wait for the screenshot to be generated, based on the time set up on the Additional wait time, and confirm that this resolved the issue.