Network Connection Problems and Remedies

This section describes the causes of network connection problems, and how to resolve them.

The machine automatically connects to a destination other than the intended destination via its dial-up access (when a dial-up router is connected to your network).

Detailed information concerning the machine cannot be set.

Unable to Set up a Network

Cause	[Confirm Network Connection Set. Changes] is set to 'Off'.
Remedy	Set [Confirm Network Connection Set. Changes] to 'On'.

The machine automatically connects to a destination other than the intended destination via its dial-up access (when a dial-up router is connected to your network).

Cause

The machine periodically or temporarily communicates with devices on your network. If a dial-up router or NetWare file server is on the network to which the machine is connected, the machine connects to a destination other than the intended destination, depending on the settings of the machine or dial-up router. This may result in subscriber line charges and call charges.

Example:

The file or mail server's host name or IP address set on the machine does not exist on the network.

The DNS server exists on an external network.

You attempt to access a device connected to an external network, if the device's information is set on the DNS server on the network to which the machine is connected.

Remedy

Check the following:

If the dial-up router does not have to send packets via broadcast, change the router settings to ensure that it sends packets via a method other than broadcast. If dial-up router has to send packets via broadcast, check that the settings are correct.

Check that the file or mail server's host name or IP address set on the machine is correct.

If you attempt to access a device on the network to which the machine is connected, with the DNS server on an external network, set the destination using an IP address, not a host name.

If information about a device on an external network is set on the DNS server on the network to which the machine is connected, check the settings.

Detailed information concerning the machine cannot be set.

Cause 1	Communication via the IP address of a computer on which you intend to use the Remote UI or utility is not permitted in [Firewall Settings] on the Network screen.
Remedy	If communication via the IP address of the computer on which you intend to use the Remote UI or utility is not permitted in [Firewall Settings] on the machine, you cannot browse information pertaining to the machine or configure the settings. Configure [Firewall Settings] on the machine so that communication via the IP address of the computer on which you intend to use the Remote UI or utility is permitted. (See steps 13 to 14 in "TCP/IPv4 Settings," or steps 9 to 10 in "TCP/IPv6 Settings.")
Cause 2	[Dedicated Comm. Settings] or [Dedicated Port Settings] is set to 'Off'.
Remedy	Specify the following settings according to "Communication Environment Setup." Press [On] for <Use SNMPv1> → [Dedicated Comm. Settings]. Press [On] for <Dedicated Community> → [Read/Write] for <MIB Access Permission>. Press [On] for [Dedicated Port Settings].
Cause 3	The SNMP community name does not match.
Remedy	If you use an SNMP community name different from the one stored in the machine to access the machine from a utility, the utility will not detect the machine. In this case, check the SNMP community name. (See "Communication Environment Setup.")
Cause 4	Invalid cache data is remaining.
Remedy	If the Remote UI does not start properly and an error message appears on your Web browser, delete the cache files.
Cause 5	[Sleep Mode Energy Use] is set to [Low] and the machine is in the Sleep mode.
Remedy	Press (Energy Saver) to cancel the Sleep mode, or set [Sleep Mode Energy Use] to [High]. (See "Energy Consumption in the Sleep Mode.")