I have configured my capsule to operate the guest network option, and now can’t access my sonos system.

If the Time Capsule was originally configured to operate in the Off (Bridge Mode) setting, then that is likely the correct configuration for the Time Capsule based on the type of modem that you have.

Was this the case?

What is the make and model number of your "modem"?

How would I know how the time capsule was originally configured?

You told us that......

I've recently configured my time capsule to allow people onto the guest network. To allow access to the guest network, I've had to select 'DHCP and NAT' in the network options (off (bridge mode)) wont allow access to the guest network.

This does read as if you recently changed the configuration on the Time Capsule to allow people on the Guest Network.

And, to do this.....you made a change to select DHCP and NAT in the network options.....since Off (Bridge Mode) was not allowing access the Guest Network.

So, what I was asking was whether the Time Capsule was originally configured to operate in (Off) Bridge Mode...... and you then later changed the setting to DHCP and NAT to activate the Guest Network.

If you did do this, you would have seen a message about a Double NAT error on the network.

Please clarify on that.

Thanks for the clarification.

When you had the Time Capsule setup to operate in Bridge Mode, the Technicolor modem/router was providing DHCP and NAT services for the entire network.

So, when you set up the Sonos system, the Sonos device was configured to receive DHCP and NAT settings from the Technicolor modem/router.

In Bridge Mode, the Time Capsule simply passes through the settings that it receives from the Technicolor modem/router to the Sonos controller.

When you changed the setup of the TIme Capsule to also provide DHCP and NAT services, the Sonos system could then no longer receive DHCP and NAT settings from the Technicolor modem/router.

So, you have a couple of options:

1) The simplest option is to change the Time Capsule back to its original Bridge Mode settings, so the Sonos system will then pick up DHCP and NAT information from the Technicolor modem/router.

The downside....you lose the Guest Network option on the Time Capsule. Maybe you could use the Technicolor modem/router to supply the guest network function?

2) If the Guest Network option on the Time Capsule is important to you, then you will have to start all over again from scratch on the Sonos System and configure it to work with the Time Capsule to pick up DHCP and NAT from the Time Capsule.

I don't have a Sonos system, so I cannot tell you that the Sonos would work correctly in this type of arrangement. Technically, it should, but as networks go, you really won't know if this will work correctly or not until you try.

The downside.....you are trying to run two routers on the network in this type of setup, with both trying to provide DHCP and NAT services.

Normally, you only want one device on a network providing DHCP and NAT services, because the network runs more efficienty this way, with much less chance of network conflicts and errors.