I am using LR 6.2.1 on Windows 7. I have been using the software since V1.0 without any major problems.
Since updating to 6.2.1 some imported images (including RAW files from Canon 5DS and 1D4 and JPEG from I Phone 5s) become blacked out when I try to edit them in LR. I have tried removing them from the LR Cat and re-importing them without success. The images are not corrupted as they can be viewed and manipulated in other software.