I have a Motorola G2. I'm unable to to access contents of external SD from PC. I chose MTP option for USB configuration. I can access the internal storage but not the external storage. The latter is shown as blank, nothing to display in SD card – but it displays the size of SD card.
I already checked solutions available for SD card not showing files when connected to pc to no avail.
I also tried to clear the cache of media storage and external storage app from Settings › Apps.
The simple way (for Lollipop and older versions): power down the Android device, remove the micro-SD, and connect it to the computer via a memory card reader. Once you're done with whatever you're doing (copying music/photos, for instance), put the card back into the device and power back up.
As noted in comments, however, on Marshmallow, this only works if the storage is being used as "external"; if it's been "adopted" as internal storage, its contents can't be read except by the adopting device.
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