Default No access to the external sdcard

Hi there.

Device: GT-9505 jfltexx (jflte)
ROM: SlimKat build 4
Kernel: ROM stock kernel

The problem is that I can't activate the external sdcard from Settings/storage. When I press "Activate sdcard" the "Preparing sdcard" notification appears in the status bar but it never ends successfully, so extsdcard, sdcard1 and other else folders are empty.

The point is that external sdcard is accessible via recovery, I can restore and so on from it, but I don't find the way to make it readable into the ROM. Any help will be much appreciated. Thanks in advance.

P.S. Just flashed the ROM and Gapps after using the "Clean to install a new rom" feature in Philz Recovery. I haven't done anything else.
Device: Samsung Galaxy S4 I9505
ROM: SlimKat build4 Stable
Kernel: ROM stock kernel
Recovery: PhilZ Touch

Device: Samsung Galaxy S II I9100
ROM: Rootbox 4.0 (from sources)
Kernel: Rootbox stock kernel
Modem: LS8