Hello Roland,

be aware that in low end Cisco Switches there is a limit in the number of STP instances that can run on the device.

There is a limit in the maximum number of vlans that can be defined but it can be higher.

To make an example I used some 29xx there was a max STP instances of 64 and a max vlans of 128.

Vlans in excess of first number can be defined but their STP instance is automatically disabled so you can see a configuration like that even without a human configuration.

You can check how many vlans are defined on the switch with

sh vlan

and status of STP with

sh spanning-tree summary

There was a similar thread some mounths ago with the same scenario: someone starting to manage a network with this kind of strange commands combination

Hope to help

Giuseppe