Sounds like Lightrom can't find the photos.
Are the photos in the same location as they were for PSE? Did you move or rename them (or the folders that contain them)? For Windows, is this an external drive? If so, did the drive letter change?
What operating system?
Thanks for the reply
My photos are on the same location as for PSE - I have no problems getting the photos on PSE and working with them.
I did not rename the photos or the Folders.
My photos are stored on a home network, external drive - NAS and I am not aware of any drive letter change. I figure if I am not experiencing any difficulties accessing my photos in PSE that the issue is with Lightroom.
My operating system is Windows 7 Home premium, 64 bits.
The LR catalog upgrade from PSE doesn't recognize the locations of photos stored on NAS:
Two possible workarounds:
1. In the left-hand Folders pane of LR, if the parent folder on the NAS containing all your pics' subfolders isn't showing, select one of the folders, right-click it, and do Show Parent Folder. Keep doing that until the root folder of all your pics' subfolders is showing. Then right-click that root folder and do Update Folder Location and select the correct NAS location.
2. If that doesn't work, in PSE 6, move all the photos to a local drive. Then in LR upgrade the PSE catalog. In LR, move all the photos back to the NAS. (Painful.)