USB drives not showing in finder

That's a tough one, because everything seems normal (btw, did you install any Lexar software?).

I'd've said, try a different brand, but you've already tried that.

Let's try to isolate the problem. In Terminal, issue the command

$ diskutil list

(where $ is your prompt). Does the listing contain anything that could be the USB drive? If yes, please post it.

Unfortunately, I don't know what the problem is, so the following is a bit of a scatter-gun approach.

Self-powered hub.

It is possible (not likely, perhaps a tad more likely if your MBP is a 13″ one) that there's an issue with USB power. If you have one, try connecting a thumb drive through a self-powered hub, ie, one with a separate power supply (not a bus-powered hub).

New user.

Create a new admin user account. Restart and log in as the new user.

Try a thumb drive. If it shows up in Disk Utility, no need to perform the other steps.

Safe Mode.

Shut down, then start in Safe Mode, as described here

<http://support.apple.com/kb/HT1455>

Try a thumb drive again. Then restart as usual (the first start after Safe Mode takes longer; that is normal). Try the thumb drive once more.

Reset NVRAM.

It is possible (not likely) that a setting in NVRAM is causing an error. Follow the instructions here

<http://support.apple.com/kb/HT1379>

to reset NVRAM.

Reset the SMC.

Follow the instructions below

<http://support.apple.com/kb/HT3964>

Hi, I've been struggling with the same problem, and have now resolved it. It was a simple configuration issue. Firstly, the Devices group was not enabled in the sidebar, so that was fixed via Finder Preferences -> Sidebar. But even though devices now showed up, it didn't show any.

The problem was that somehow I had asked the machine to hide them. By placing the cursor just to the right of the word "Devices" in the sidebar, I had the option to Show (it had been set to hide).

Hope this helps someone to save the hour and half it took me to fix it 🙂

Thanks for posting this, Govigs.

I never would have found the "show" link without help.

Glad I found this. Problem solved. Thank you!

I had this problem and first checked my preferences but it was all fine with all drives checked to be shown. So I next tried repairing the Main Drive via Disk Utility. It claimed all was fine. But as soon as it was done I popped out the USB drive, popped it back in and VOILA, it finally showed up!

Try this:

1. You have your Finder Window open

2. Open another program that allows you to insert pictures or files. For instance, Powerpoint (yes, on a Mac I have powerpoint)

3. Click insert picture from file

4. This opens a view similar to Finder. Look on the left hand side for DEVICES and select your MacBook. This should list your HD, Network and any USB or external devices connected.

5. Click the USB drive from this window and drag it over to Finder.

6. It should show up under DEVICES in your Finder now.

I found your question because I had the same issue. A functioning USB stick that was invisible. Btw, the Mac Pro is running Mavericks. Of all my sticks only the 32GB FAT32 one was invisible to Finder and Disk Utility. It was very happy on a Windows platform. The answer, and it's unlikely to be given lots of 'Likes', lay in the volume label. It is a USB stick that I use to play music in my car. I had labelled it with my postcode preceded by the house number: #7KT123XY in the vain hope that were it to be found by some kindly soul, it could be returned.

On a whim I changed the label to 7-KT123XY and now OS X is entirely happy with it.

I expect an OS X guru will be able to explain the bleeding obvious reason to me as to why a # makes devices invisible, but it's not something I could even begin to help you with. I'm inclined to suggest it's an "undocumented feature".