wwe
2
welcome to the forum @rippletide 
Please use the search, most of the problems have been discussed already!
# for docker
docker exec --user www-data <nextcloud container name> php occ config:system:set allow_local_remote_servers --value true --type bool
# native install (sudo might be required)
php occ config:system:set allow_loca_remote_servers --value true --type bool
See below: