Thiscan also beis usually due to a disk problem so I recommend running the disk repair utility in maintenance mode. Since the web interface isn't working, you'll need to use the telnet menu to enter maintenance mode and run the check.
Did you repeat the re-install of the web interface after installing jim-xconv?Ran this command successfully but still even after reboot - only see top banner on the web interface.
The strange xconv log entries when installing Webif persist.Try running this from the command line:
Code:opkg install jim-xconv --force-reinstall
require system.class
in /mod/sbin/autoschedule
.