If "webMAN Games" folder does not show:
1- it is possible that category_game.xml was replaced. fix: reinstall HEN.
2- the plugin may not be running. fix: check that there is not a boot_plugins.txt in USB; reinstall wMM.
If "webMAN Games" folder shows, but there are not folders inside:
1- the settings may have some categories unchecked. fix: delete /dev_hdd0/tmp/wm_config.bin to restore the default settings or verify that game categories are selected in
http://0/setup.ps3
2- the folders or the ISO images are not properly named. fix: check that the folders are /PS3ISO, /PSXISO, /PSPISO, /BDISO, /DVDISO (the folder names should be in uppercase). And the file extensions are: .ISO, .iso. For PS2 games should be stored in /dev_hdd0/PS2ISO and the extension should be .BIN.ENC
3- the USB could not be detected. fix: check that the USB storage device is formatted as "MBR" in FAT32, NTFS or exFAT. Verify if IRISMAN can read the USB device. Also try copying some games to dev_hdd0 to check if they are listed.
4- If you use prepISO you may need to uncheck the option "/dev_ntfs" in /setup.ps3
That option -when checked- allows to scan NTFS devices without require prepISO or prepNTFS.
5- If there is a large number of games in the USB storage device, you may need to reload XMB to display the scanned games after launch prepISO.