Field workers today are, quite frankly, spoiled.
The devices we use to connect to the Internet while on the move are becoming increasingly faster, easier to install and easier to use. It is easy to forget to days of dial-up connections, of manually editing initialisation strings to set your device to a precious HSCSD as opposed to plain old CSD mode…of having to actually ‘make it work’.
I thought it would be worth a blog post to remind readers that even today, sometimes things just ‘go wrong’, and you may need to troubleshoot the problem before your new all-singing, all-dancing device will connect you to the Internet.
In the event of everything not going according to plan, there are 3 main areas that could be the cause of the problem:
In this article I will look solely at PC cards and USB devices. Whilst Bluetooth and Infrared connections are still used, the limitations of the inter-device connection speed render them arguably unsuitable for today’s data rates, after the ‘data overhead’ of encryption and error correction is taken into account.
Before I look at how hardware installation problems are identified and resolved, it is perhaps necessary to first briefly go over how current PC hardware “hangs together”.
For the purposes of troubleshooting new plug and play hardware, suffice it to say, and this is a vastly oversimplified description, that a PC, consists of a processor (CPU or Central Processing Unit), a BIOS (Binary Input Output System), a data bus, some memory and some expansion ports.
The “heart” of the PC is the processor, which receives commands from the various input devices connected to the PC (keyboard, mouse, etc) and returns responses to the output devices (monitor, printer, etc). The processor is connected to the “data bus”, as are all the other devices that need to be able to communicate with the processor.
In order for the processor to “know” which device is communicating with it at any given time, each device is assigned its own “interrupt”, so that it can interrupt the processor from what it is doing and request its attention. Each processor will have a limited number of interrupts available. The information regarding which interrupt is used by which device is held in the BIOS, which is accessed when the PC is turned on, or “booted”. Having more than one device configured to use the same interrupt can cause devices to malfunction.
When installing new devices, it is imperative that you read the manufacturer’s documentation before proceeding. In all cases, if a device comes with a CD you should insert the CD into the PC before inserting the new hardware!
When the new hardware is inserted, Windows will normally indicate that it has detected the new hardware by displaying an icon in the system tray, and will also indicate when the installation process has completed.
As a rule of thumb, even if not prompted to do so by the manufacturer’s installation wizard, it is always a good idea to restart the PC after installing new hardware.
Once installed, verify that the new hardware is installed correctly by looking in the Device Manager. On Windows XP, this is done as follows:
Normally, you should not see any items with a red X or a yellow exclamation mark, and there should not be a section entitled ‘Other Devices’ (which would indicate that the operating is unable to determine what that particular element of hardware is):
On Windows Vista, the Device Manager is launched as follows:
Should you see any item with either a red X or a yellow exclamation mark on it, which looks like it may be related to the new hardware you’ve just tried to install, then there has been a problem during the installation. Typically, GPRS / 3G devices will install themselves as modems and network adapters.
The first step at this point would be try completely uninstalling the software via the Add/Remove Programs applet in the Control Panel, rebooting the PC, and then reinstalling it again.
Should that not resolve the problem, then it is possible that the PC does not have enough free interrupts available to install the new hardware. If this is the case then you will first need to disable another device before installing this one. Typically infrared ports, or internal 56K modems are not used, so one or even both of these could be disabled – this will need to be done in the PCs BIOS: consult the manufacturer’s documentation for your PC before changing any settings in the BIOS.
I have assumed so far that when the new hardware was inserted, Windows detected and tried to install it. If nothing happens at all, verify that, in the case of USB devices, that the USB section in the device manager is present, and listed with no errors, and similarly the PCMCIA section for datacards.
If you’re using a laptop in a docking station, try undocking the laptop and inserting the device directly into the laptop.
It is also important to note that when installing new hardware you will need administrative rights on the PC – so if you’re using a company machine you may need to get the network administrator to install it for you.
Of course, if you have checked all of the above and the device still fails to install correctly, it is possible that either the device or the PC is faulty. Try another PC if possible, if the device fails to install on that machine also, then consult the vendor.
Once the new hardware is installed, the appropriate accompanying software needs to be used to initiate the Internet connection. This software may need to be configured with the correct connection settings for your network operator. You should not need to change any of the default settings, other than the Access Point Name (APN), Username and Password. The settings for the most common UK networks are as follows:
APN – internet
Username – web
Password – web
APN – orangeinternet
Username - (leave blank)
Password - (leave blank)
APN – mobile.o2.co.uk
Username – web
Password – web
APN – general.t-mobile.uk
Username - (leave blank)
Password - (leave blank)
APN – three.co.uk
Username - (leave blank)
Password - (leave blank)
Provided that the correct settings have been entered, if the connection fails, make a note of the error message that is returned.
An error along the lines of ‘the answering modem failed to respond’ could mean that the APN has not been entered correctly and that the settings should be double checked.
It may also be the case that although the settings are correct, the SIM is not enabled for the service that is being accessed, and a call will need to be made to the network operator to get the service activated.
An error indicating that the modem is busy, or is already in use, could indicate an interrupt conflict, or could mean that another application is running that is trying to access the device – fax software which has been configured to automatically answer incoming faxes can cause this. For USB devices, try to disable any software that may be set to monitor USB connections – synchronisation software for a PDA, imaging software for a scanner, USB printer management software, for example.
Should everything appear to be configured correctly, but the connection still fails, it is time to roll up your sleeves, as it were.
Close the software for the mobile device.
Launch an application called HyperTerminal.
Depending on which version of Windows you are running, this application lies in a different place in the Start menu, so it is easier to launch it by clicking on Start and selecting Run. In the Run dialogue, type in:
and press enter. This will launch the HyperTerminal application. If this is the first time you are running the application, you may be prompted to set the program as the default Telnet application, just click OK. You may also be prompted to complete your telephone number details, just complete the area code field and click OK.
HyperTerminal will now launch, and you will be prompted to enter a name for the session. Just type in ‘Test’ and click OK.
You will now be prompted to enter a telephone number, just enter 0. You will also be prompted to select a connection device, here it is vital that you select the GPR / 3G modem that you wish to troubleshoot. Click OK.
On the next screen you will be prompted to Dial, DO NOT dial, just click Cancel.
You will now be presented with a blank screen and a flashing cursor.
It is now possible to issue what are known as “AT” commands to the device (so called because they all begin with the letters AT). Type in the following commands to ascertain the status of the device:
Should return OK. If you are not able to see what you are typing on the screen, type in
This should return OK, and will turn on the ‘echo’ so that you can now see what you type on the screen.
Should return the network operator. NOTE - if this command returns an error, it may be necessary to activate the radio on the device. This can be done by entering
Which should return OK after a few moments. Now trying issuing AT+COPS? again. Should you still not be registered with the network operator, it may be necessary to enter a PIN code to enable the SIM card. This can be checked by typing
This will return whether or not the SIM requires a PIN code
indicates that a PIN code is required. To enter a PIN code type
(where xxxx is your 4-digit PIN)
+CPIN: SIM PIN
indicates that there is no PIN code required
indicates that the SIM cannot be read
If the device does not require a PIN to unlock it, and still does not register on the network, it may be that the device is locked to a particular network and cannot be used with your SIM card. This can be checked by typing:
This will return whether the device is network-locked or not:
0 – unlocked
1 – locked
If the device does not require a PIN, and is not network-locked, and yet still does not register with a network operator, then you can query the registration status of the device by typing:
This will return the network registration status:
0 - not registered, not searching
1 - registered, home network
2 - not registered, searching
3 - registration denied by network
4 - unknown
A response of 0 would indicate that the device tried to find a network but was unable to. This might indicate a faulty aerial on the device, or a lack of available signal.
A response of 1 would indicate that the device believes that it is registered.
A response of 2 would indicate that the device is still searching for a network. This might mean that you simply need to be patient, or may mean that there is insufficient signal available.
A response of 3 would indicate that either the device or the SIM has been ‘blacklisted’ by the network. This could indicate that the device is stolen, the bill has not been paid, etc. In any case, a call should be made to the network operator to establish why.
Provided that the device is registered on the network, it is possible that the device is registered for voice communications, but not for data. This can be verified by typing:
This will return whether the card is attached to the packet data network or not
0 - detached
1 - attached
It is possible force a connection to the data network by typing:
Provided that you are registered on the network and are attached to the packet data network, you can then enter the APN of your network provider. This is done by typing:
(where APN is the Access Point Name for the network operator, as defined above)
This will return OK (Note – IP needs to be capital letters for most devices)
Once the APN has been defined, it is now possible to initiate the connection. This is done by typing:
The device will now connect to the Internet. If you see the word CONNECT in the Terminal window, then the connection has been established.
If the connection fails then it is possible that the SIM card is not enabled for the service that is being accessed and you will need to contact your network operator to get the service activated.
If you have run through all of the above, and are able to connect to the Internet, but once connected you are not able to view any web pages, or send and receive email, then it is possible that DNS server settings need to be configured.
DNS is the Domain Name System and is responsible for converting the “friendly” names of web addresses (www.bbc.co.uk, for example), which are meaningless to computers, to their corresponding IP addresses (126.96.36.199), which they do understand. If the PC is not able to contact a DNS server, it will not be able to resolve the web addresses that you enter.
A DNS issue is easy to identify: if entering www.bbc.co.uk into a web browser does not display the BBC Homepage, but yet entering 188.8.131.52 does, then it is a DNS issue.
Similarly, for email issues, if you are not able to send or receive email, try substituting the “friendly” name of the email server for its IP address.
The IP address of a server can be identified (on a PC which IS able to contact a DNS server), as follows:
The IP address will be returned:
It is not normally necessary to manually configure DNS server settings, but should you identify that this is the problem, then your network provider will need to provide you with the correct settings to use. Alternately, Google now provides an external DNS service:
These addresses will need to be entered within the manufacturer’s connection software.
If you have run through all of the above troubleshooting and both the device and SIM appear to be working correctly, then it is possible that there is a fault with the mobile network, or for some reason your account has been altered by the vagaries of the customer service department. In either case, a call to the network will be necessary!
If you are experiencing an issue whereby you are connected to the Internet and can browse web pages, and are able to receive emails, but are not able to send emails, it is likely that you will need to change the SMTP server address in your email application.
If you use a POP/SMTP-based email solution rather than an Exchange or Domino-based solution, most SMTP servers are configured to only allow emails to be sent through them from a known list of IP addresses, to prevent SPAM. You may well be able to send emails from home via your broadband connection, but not when connected to the Internet via your mobile network provider.
In this situation you will need to create a new mail profile (or edit your existing one if you are willing to each time you need to), and set the SMTP server address to the SMTP server provided by your network provider - if they have one (most do, if they do not I would advise moving provider). Customer services will be able to provide this information.