I want to back up photos from PC to external HD. When I try to do this through Lightroom it as 95% of the photos grayed out. when I click on one of them it says they have already been imported. They are not on the external HD and never have been. The only thing I did recently was add the photos from the PC to the LR catalog. Any ideas? Thank you.
You mentioned that you have added the images from PC to the catalog which means the images are already present in catalog and that is why they cannot be imported.
Are those images same on your PC local drive and on your external drive?
Do you want the images to be linked to the catalog from external drive and not from PC Drive?
Which version of Lightroom do you have?
You can't use Lightroom to back up photos. Re-importing them will not make a backup.
Your photos are not "in" Lightroom, they are in folders on your hard drive.
Lightroom only makes a reference to them in the catalog.
Use Windows Explorer to copy the photos to the external drive, or use a backup utility