Happened me also. Just was getting used to the SDK and Scenery Dev, as Ireland, pretty much non existent in MSFS bar one or two ‘efforts’. No landmarks what so ever in City, nor ‘Twin Towers’ (Pidgeon house generating station) in the bay. A massive work in progress for myself (when MSFS working). Save your files/projects to a separate directory, even copy and paste to external HD, when sys. reinstalls, copy them back, keeping an external hard copy of your files and projects, in case of further issues. ( In fairness, a platform such as MSFS, never before been done, bound to be the odd hi-cup)