Class Magento\NewRelicReporting\Model\Apm\DeploymentsFactory does not exist
After upgrading from 2.0 to 2.02, the system has become unstable. This particular error occurred after touching the Config/Developer options, to see if that might help narrow down the numerous "Object DOMDocument should be created." errors that have cropped up both in the store and the administrative site following the upgrade.
If anyone has any suggestions, I'd love to hear them. I saw a few answers on the Internet regarding the Object DOMDocument, but they were too vague and general to be of immediate help.At this point, I think there's not much choice but to do an entirely fresh install of 2.02 and retrod over the ground already covered. Fortunately, the store hasn't yet been opened for business.
Hi, I did encounter similar issues a couple of times, due testing the Magento 2.0.x I installed in the past month over 25 times on different hardware and configurations, such issues like missing buttons in back admin, or white screen during cash flush or error for missing modules/ components are very annoying, however I think most of the time the issue is at least based on my experience due error during the installation process. I don't know if something is skipped during the install and upgrade of the components, but today I had exactly the same issue with missing buttons for products, categories, and attributes, also when I try to press flush magento cache button I was trow on white screen with error for missing components, so the easiest step
2. install it again always till now the second install is working great and all that was missing is fixed
P.S> Actually I continue to encounter issue with missing components, even after on a first look successful reinstall, i found a fresh article that in case you work in default mode most of the components DO NOT generate for you automatically so you need to do that manually, after i did that all the errors related with missing components disappeared.