When pushing out the configuration from the HiveManager to Aerohive APs, and you have one or more captive portal in use, the update may fail with an error about unable to upload the captive portal files. The detailed error message reveals a problem with SCP (such as not enough free space to store files).
The problem is that the "web-directory", a local folder in the AP is taking up too much space on the flash memory. You can completely clear the folder through the CLI, then have the update put the captive portal files back.
# clear web-directory