On a DP752, the base handles the Internet connection and SIP account while a compatible handset connects to it over DECT. This article follows the DP752 interface, not the different DP755 layout. Keep the handset’s pairing status separate from the account’s SIP registration status when diagnosing a problem.
Prepare the IllyVoIP line
Open SIP Lines and obtain the SIP username, SIP password and server for the line you intend to connect. These are not your Portal email and login password. This walkthrough uses password authentication. If the existing line uses IP authentication, do not switch modes without checking which devices depend on it.
A separate device can use a separate SIP line; review any subscription charge before confirming. Keep a note of which device uses each line, but do not put passwords in shared documents. When replacing a working phone, keep its configuration privately so you have a way back if the new setup needs troubleshooting.
Plan a simple first setup
For the first test, use one handset, one IllyVoIP line and one unused profile/account combination. Note the handset identifier so you do not accidentally assign another employee’s handset. If the base is already in service, changing a shared profile can affect other accounts: use the administrator’s agreed configuration instead of overwriting it.
Configure the profile and account
After pairing a compatible handset using the device guide, open the base’s local web interface as administrator. Under Profiles → General Settings, activate the intended profile and enter the SIP Server. Save and apply. Next open DECT → SIP Account Settings, activate an account and fill its SIP credentials. Select the same profile you just configured.
| Field | What to enter |
|---|---|
| SIP User ID | IllyVoIP SIP username |
| Authenticate ID | SIP authentication ID |
| Password | SIP password |
| Profile | The profile containing your IllyVoIP server |
| HS Mode | The intended handset or deliberately chosen hunt mode |
Assign the account to the handset
In DECT → Handset Line Settings, assign the account to the intended handset. Check Status → Account Status for SIP registration and assignment. A profile defines connection settings; it is not itself a handset assignment. A handset name on screen is also not proof of an external connection.
A practical two-handset example
Suppose you want calls to reach Reception, not the stockroom. Start with a specific handset assignment rather than a hunt group. Once both call directions work, decide whether a second handset should ring as well. The base offers hunting behavior, but changing it is an office call-handling decision, not a requirement for basic registration. Confirm the result from another phone rather than relying on how the settings look.
Registered, but calls go to the wrong place?
Check three things in order: the number’s destination in IllyVoIP, the account selected on the base, and the handset assigned to it. For outgoing calls, verify the selected/default handset line. If the right handset rings but the wrong outgoing identity is used, changing the number’s incoming destination will not fix the outgoing selection.
If a second simultaneous call fails, check the account’s allowed capacity before adding credentials or enabling a hunt mode. More paired handsets do not automatically increase your service limits. Keep the first successful call as a baseline and change one assignment at a time.
Match signaling and audio settings
Use the server, destination port and transport supplied for your line. The device’s local IP opens its administration page; it is not the IllyVoIP server address. SIP signaling and audio encryption are separate choices. The Portal audio mode must match the device’s supported configuration: Standard RTP, SDES-SRTP or DTLS-SRTP. Do not change encryption just because an unrelated tutorial uses another setting.
Keep the administration page on a trusted network. Do not expose it to the Internet or disable a firewall to make a test work. If your model does not offer a required option, ask about that exact model and firmware instead of changing several unrelated settings at once.
Verify the result one step at a time
- Registration: check the device’s account status. A familiar name on its screen is not proof that it is registered.
- Outgoing call: select the IllyVoIP line and call a number you control in international format. Check balance and destination rates first; the test may be chargeable.
- Audio and identity: speak in both directions and check the outgoing caller ID. Editing a local display name does not grant permission to use another number.
- Incoming call: route an active phone number to this SIP line and call it from another device. SIP registration does not automatically choose a number’s incoming destination.
What to check before contacting Support
If registration fails, check the line details before changing the network. If registration succeeds but a call is rejected, check number format, balance, routing package and permitted caller ID. If the call connects without audio, report that distinction: it is a different problem from failure to register.
Include the device model, firmware version, time and timezone, visible error and public call reference where available. The SIP response-code guide helps explain errors. Never send passwords, unmasked configuration exports or screenshots containing customer data.
Documentation and scope
Device configuration reference. Menu paths were checked against documentation and Portal steps against IllyVoIP. This is not physical-device certification; the Portal screenshot is not a screenshot of the phone administration interface.