Change NAT issue pfSense 2.3.4

[dt8tsh]

Can someone help me. I'm getting a fatal error when updating NAT on pfSense 2.3.4:

/firewall_nat_edit.php: New alert found: PHP ERROR: Type: 1, File: /usr/local/www/firewall_nat_edit.php, Line: 301, Message: Call to undefined function is_port_or_alias()

can someone help me?

I looked upon the internet and the only solution that I found has something to do with the disk:
https://forum.pfsense.org/index.php?topic=131078.msg721540#msg721540

but my disk is ok I guess.

[jimp]

That function is in /etc/inc/util.inc which there wouldn't be any way to skip just that one function in that file, and that file is loaded on every page that uses the configuration libraries (which is every page used by the GUI, essentially)

Of the possible explanations, a corrupted filesystem or failing disk are most likely. Especially if it happened out of the blue without any action on your part causing it.