Lightroom CC - Import Fail

This has happened occasionally in the past with 1 or 2 images, but today when importing about 200 images from a from an

SD card, about 50 images failed to import. After restarting the import feature, the remaining images successfully imported

into Lightroom. Is this normal? Is there anything I can do to so that this does not happen again? I am using Lightroom CC

2015.7 and importing .ORF (Olympus Raw) files from a Transcend 16 mb SD card. There is no sign that any of the 50 files

are corrupted in anyway.

<p>Assuming the card itself is OK (and that's a big assumption), you may have either 1) a failing card reader or 2) a bad memory module in the computer. I've actually had issues over the years caused by each of those - card, card reader, RAM.<br>

<br />You didn't say what platform you're on, but Apple's got a built-in memory tester on the Mac, and there's the "Windows Memory Diagnostic Tool". I've had faulty RAM that was not significantly impacting other computer functions because of the type of error and where it was located on the memory module - cause this.<br /><br />I'd run the memory diagnostic first - if you've got RAM problems, every other diagnostic is potentially suspect. Assuming that passes, you need to test the card and card reader. (If you're being especially thorough, you could test the computer's hard drive after the RAM test. Just make sure you don't select a destructive test!)<br>

When testing the SD card - note that a decent test of the card may be a read/write test - make sure you have no data left on the card that you want to keep.<br /><br />If possible, do read/write testing on a different SD card (one you believe is OK) on the same card reader. There are a few test utilities out there, depending on platform. If you end up with problems on every card you test, it makes it more likely it's the card reader (or the cable).<br /><br />If the card reader checks out OK, re-run the testing using the card that failed.<br /><br />If you still haven't found anything, you need to keep an eye on it - if the problem is intermittent, it's likely to get worse, which will at least make it easier to find.<br>

Also, think about whether or not you've seen other computer issues - crashing programs, operating system exceptions, etc. with any increased frequency of late. That would tend to point more towards a system problem, than the card or the card reader.<br /><br />Make sure you've got a current backup! Something that generates checksums and compares the copy with the original wouldn't be all bad in this situation. If you're getting read/write errors of unknown origin, you're in "trust no one" territory.</p>

Thank you for your detailed answer! I am using an aging WIN 7 HP mini tower and the SD card reader that is

built into the computer. The system runs diagnostics weekly and has never failed. This morning I ran a full

system diagnostic, an additional memory test, and a test of the SD card reader. All checked out OK. I will look

to find an application that will check the SD cards themselves, though I don't believe the current diagnostic

program I have can do this. I run a backup regularly, though I don't know if the back-up application (that came

with the 1TB HP external drive) generates checksums. At this point I would guess the culprit is either the card

or the card reader.