I think you have a misconception of LR and the CC programs. Just because the newer versions of Adobe software is called Creative Cloud doesn't mean all the images you have imported into LR are stored in the clouds on some Adobe server. They aren't. They never leave your computer unless you have a cloud storage system that you subscribe to, Like MS OneDrive, Google Drive and others, and that you have specifically Uploaded your images to for Backup Storage. All your images are stored on the drives connected to your computer. Whether those drives are internal to your computer or connected externally.
So if you wiped your internal hard drive to do the reinstall of Windows and your programs, including the Adobe CC programs like LR, and that was where you had originally stored your images then all your images are gone. That is unless you manually created a backup of them on an external drive or you do have one of the Cloud based storage system that you uploaded your images to.
If you have them backed up on an external drive or in some cloud storage service then you will have to first download them from the cloud storage service and Re-import them into a new LR catalog (that is if you don't have a backup of your original catalog file) or connect your backup external drive and do the same.
Please be more specific in what you did when you had to reinstall Windows. And include whether or not you have backups of your images on external drives or in some Cloud storage system.
Thanks for you feedback. However, I can log into my Creative Cloud account and all of my photos and collections are there. I can view and edit them etc. What I cannot do is to download these images to my desktop app. Tried all the syncing steps, etc but there appears to be no way to restore the photos online with my desktop app.
Those images stored in your CC account area are small copies of images you synced with LR Mobile. For the purpose of syncing with LR Mobile They allow some edits which are stored someplace, not sure where, and when you sync up the desktop app with LR Mobile again those edits are applied to the REAL images stored on your computer. Otherwise Adobe would need Terabits of Terabits of Terabits, sexdecillion (10 to the 51 power), of storage space to store all users images that use LR and LR Mobile.
Since I don't use LR Mobile (and find it a Bad joke played on users. Kind of what you are finding out) I have no idea how and if you can download those images to your computer. Have you tried selecting some and right clicking and selecting Download (if that is an available option) or in one of the menus in the web interface? You would need to download them to a folder on your hard drive and then import them into LR. That is unless you have local backups of your images and a backup of the original LR catalog.
Please state whether or not you had/have some type of local backups of your images or you do have some type of Online storage system other than what you are seeing in your CC account area.
Again good information. I have managed to right click and select copy then past onto my desktop which is a bit laborious but doable. Everything else especially photos and important documents I backup to MS Onedrive. I was not able to do this before my crash, so I guess I am stuck with what I get. Thanks again.