SIP24.CC — COMPLETE ZOIPER SETUP GUIDE
Android • iOS • Windows • macOS • SIP registration • Audio troubleshooting
INTRODUCTION
If you're using
SIP24.CC with Zoiper and you're having trouble getting the account registered, this guide covers the entire setup process from beginning to end.
You do
not need an advanced PBX installation to use Zoiper. Zoiper is a SIP softphone, meaning it can connect directly to a SIP account and turn your phone or computer into a softphone.
The basic information you need from your SIP24 dashboard is:
- SIP Username
- SIP Password
- SIP Domain / Host
Depending on the account and network configuration, you may also need:
- SIP transport
- SIP port
- Outbound proxy
- Authentication username
- SRTP / encryption settings
Zoiper's own documentation confirms that a manual SIP configuration normally requires the hostname/domain, username, and password, with an outbound proxy or authentication username only when the provider specifically requires them.
1. BEFORE YOU START
Before opening Zoiper, make sure your SIP24 account is ready.
Step 1 — Log into your SIP24 dashboard
Open your SIP24 account and locate the
SIP Account section.
You should have access to the credentials required to register the softphone.
Do not confuse the following information:
- Website login — used to access your SIP24 dashboard.
- SIP username — used by the SIP client to authenticate.
- SIP password — used by the SIP client.
- SIP domain — the SIP server/registrar.
Your SIP credentials are what belong inside Zoiper.
Do not enter your website email, dashboard password, Telegram username, or other unrelated account information unless specifically instructed.
2. INSTALLING ZOIPER
Zoiper is available for multiple platforms.
- Android — install Zoiper from Google Play.
- iPhone / iPad — install Zoiper from the App Store.
- Windows — install the desktop version.
- macOS — install the desktop version.
Use the official Zoiper application rather than random modified APKs or unofficial builds.
For mobile users, Zoiper's official documentation provides separate configuration instructions for Android and iOS.
3. ANDROID — COMPLETE CONFIGURATION
Step 1 — Open Zoiper
Launch Zoiper after installation.
Depending on the version of the application, the interface may look slightly different.
Zoiper periodically changes its interface, so menu names can vary between releases.
Look for:
Settings → Accounts → Add account
Zoiper's current Android documentation describes the configuration path as:
Config → Accounts → Add account.
Step 2 — Select "Yes"
When Zoiper asks:
"Do you already have an account?"
select:
YES
You already have SIP credentials from SIP24, so you do not need to create a new VoIP account through Zoiper.
Step 3 — Select manual configuration
Zoiper may show a provider list.
Do not select a random provider.
Choose:
Manual Configuration
Then select:
SIP
Zoiper officially recommends manual SIP configuration when you already have SIP credentials supplied by your provider.
4. ANDROID — ENTERING YOUR SIP24 CREDENTIALS
You should now see several fields.
Account Name
This is simply the name displayed inside Zoiper.
You can enter:
or:
The account name does
not authenticate you to the SIP server. It is simply a label for your own reference. Zoiper's documentation specifically distinguishes the account name from the actual VoIP credentials.
Host / Domain
Enter the SIP domain provided inside your SIP24 dashboard.
Example format:
If SIP24 specifically provides a port, it may appear in the form:
Do not replace the domain with a random IP address.
Zoiper identifies this field as the hostname/domain/registrar of the SIP server.
Username
Enter the exact SIP username from your SIP24 dashboard.
Example:
Do not add spaces before or after the username.
Password
Enter the SIP password exactly as provided.
If you copy/paste it, check that you have not accidentally copied a space at the beginning or end.
Authentication Username
Leave this empty unless SIP24 specifically provides a separate authentication username.
Outbound Proxy
Leave this empty unless SIP24 specifically provides an outbound proxy.
Zoiper's own documentation recommends leaving optional authentication and outbound-proxy fields unused unless the provider requires them.
5. SAVE THE ACCOUNT
Once the information has been entered, save the account.
Zoiper will attempt to register against the SIP server.
If the credentials and network settings are correct, the account should eventually show as registered/connected.
Zoiper notes that on Android a successfully configured account can show a green status indicator after registration.
Do not immediately change ten settings if registration fails.
First check the three most important fields:
- Username
- Password
- Host / Domain
Most basic registration failures start with one of these values being incorrect.
6. iPHONE / iOS SETUP
The iOS procedure is very similar.
Open:
Settings → Accounts
Then tap:
+
Zoiper will ask whether you already have an account.
Select:
YES
Then choose:
Manual Configuration
Select:
SIP
You will then be asked for the SIP account information.
Account Name
Enter:
Host
Enter the SIP24 domain supplied in your dashboard.
Username
Enter your SIP username.
Password
Enter your SIP password.
Authentication Username
Leave empty unless specifically provided.
Outbound Proxy
Leave empty unless specifically provided.
Zoiper's official iOS instructions follow the same basic model: Settings → Accounts → Add account → Manual Configuration → SIP, followed by the provider's host, username, and password.
7. WINDOWS / MACOS SETUP
Desktop users can configure Zoiper in essentially the same way.
Open Zoiper and locate:
Settings → Accounts
Then select:
Add
Create a new SIP account.
Enter:
Domain:
Username:
Password:
Zoiper's desktop documentation describes the SIP account fields as Domain, Username and Password, with additional authentication username and outbound proxy fields available when required.
After saving, allow Zoiper a moment to register.
8. TRANSPORT SETTINGS
This is one of the settings that can cause unnecessary confusion.
SIP can use different transports, including:
The correct choice depends on what the SIP server supports.
Do not randomly switch transports simply because somebody on a forum recommended one.
If SIP24 provides a specific transport, use that configuration.
If your supplied configuration specifies TLS, configure TLS.
If it specifies TCP, use TCP.
Zoiper's documentation notes that TCP can be preferable to UDP in some environments, while TLS provides encrypted SIP signaling; TLS by itself does not encrypt the audio media, which requires a media-encryption mechanism such as SRTP.
9. SRTP / ENCRYPTED AUDIO
If your SIP24 configuration requires encrypted media, make sure the corresponding SRTP setting is enabled.
Important distinction:
SIP signaling
This handles things such as registration and call setup.
RTP media
This carries the actual voice audio.
TLS
Protects SIP signaling.
SRTP
Protects the RTP audio.
Therefore, enabling TLS does not automatically mean the voice media is encrypted.
Zoiper's documentation specifically notes that SRTP is used to protect media and that SRTP configuration depends on the corresponding encrypted transport/key-negotiation setup.
For SIP24 accounts, use the encryption settings specified by the service configuration rather than guessing.
10. FIRST REGISTRATION TEST
Once Zoiper shows the account as registered, do not immediately start changing advanced settings.
First perform a basic connectivity test.
Check:
- Account shows registered/connected.
- Microphone permission is enabled.
- Speaker permission is enabled.
- Internet connection is stable.
- SIP balance is available.
Then make a normal permitted test call.
If your SIP24 account provides an echo/latency test, use the service's documented test procedure.
The purpose of an echo test is simple:
You speak → the system receives your audio → the system sends audio back → you hear yourself.
This helps separate registration problems from audio problems.
11. "ACCOUNT NOT REGISTERED"
If Zoiper refuses to register, check the following in order.
CHECK #1 — USERNAME
Compare the username in Zoiper with the username displayed in your SIP24 dashboard.
Check every character.
CHECK #2 — PASSWORD
Re-enter the password manually.
If you copied it, make sure there are no spaces.
CHECK #3 — DOMAIN
Verify that the SIP domain is exactly correct.
Do not enter:
(https://example.com[/code)]
unless specifically instructed.
The SIP host normally looks more like:
CHECK #4 — ACCOUNT TYPE
Make sure the account is configured as:
SIP
rather than IAX.
CHECK #5 — TRANSPORT
If your provider specifies TCP or TLS, make sure Zoiper is not attempting UDP.
CHECK #6 — PORT
If the provider specifies a non-default SIP port, make sure it is entered correctly.
Zoiper documents that a port can be appended to the hostname using the format:
when required.
12. REGISTERED BUT NO AUDIO
This is a different problem.
If the account successfully registers but calls have:
- No audio
- One-way audio
- Audio that cuts out
- Audio that works only on Wi-Fi
then the credentials may be completely correct.
The problem may instead involve NAT, firewall behavior, RTP handling, or network configuration.
Zoiper's own troubleshooting documentation identifies NAT/network configuration as a common cause of one-way or missing audio.
First test:
Try the same account from another network.
For example:
Wi-Fi → mobile data
or:
mobile data → Wi-Fi
If the problem disappears when changing networks, that strongly suggests a network/NAT-related issue rather than incorrect SIP credentials.
13. RPORT / STUN / NAT TROUBLESHOOTING
If registration works but audio does not, Zoiper provides network-related settings that can be tested.
Depending on your version:
Settings → Accounts → Your SIP Account → Network
Look for settings related to:
- RPORT
- STUN
- Media handling
- Network transport
Do
one change at a time.
Do not change RPORT, STUN, transport, codecs, ports, and encryption simultaneously.
Otherwise, if the problem disappears, you will not know which setting actually fixed it.
Zoiper's Android troubleshooting guide specifically recommends testing RPORT and STUN settings when dealing with one-way or missing audio.
14. DO NOT ENABLE RANDOM STUN SERVERS
STUN is useful in some NAT environments, but it is not automatically required for every SIP configuration.
If your provider gives you a specific STUN configuration, use it.
If not, do not blindly add random public STUN servers because somebody suggested them.
The wrong NAT configuration can make an otherwise functional SIP account behave worse.
15. SIP ALG
Some routers have a feature called:
SIP ALG
SIP ALG attempts to modify SIP traffic as it passes through the router.
Unfortunately, certain implementations can interfere with SIP signaling or media.
If you experience strange behavior such as:
- Calls connecting but no audio
- One-way audio
- Calls dropping
- Registration repeatedly disappearing
check whether your router has SIP ALG enabled.
Zoiper's support documentation also discusses SIP ALG and NAT-related problems as potential causes of SIP connectivity issues.
16. FIREWALL / NETWORK TEST
A very useful diagnostic is to test the account from another internet connection.
Example:
Test A
Home Wi-Fi → Zoiper
Test B
Mobile data → Zoiper
If:
A = broken
B = working
then the SIP account itself is probably not the first thing to investigate.
Look at the local router, firewall, ISP network, or NAT behavior.
If both networks fail identically, return to the SIP account configuration and credentials.
17. DTMF / KEYPAD PROBLEMS
If calls connect normally but pressing numbers during an automated phone menu does not work correctly, the issue may be DTMF configuration.
DTMF is the signaling used when you press:
For example, when an automated system says:
"Press 1 for English."
Zoiper supports different DTMF modes, and the correct mode depends on what the SIP server/PBX expects.
If DTMF is not working, check the account's DTMF settings rather than changing unrelated SIP settings.
18. MICROPHONE DOES NOT WORK
If the other side cannot hear you:
On Android/iPhone:
Check that Zoiper has microphone permission.
On Windows/macOS:
Check:
- Operating-system microphone permissions
- Correct input device
- Microphone mute status
- Zoiper audio device selection
You can have a perfectly registered SIP account and still have no outgoing audio if the operating system has blocked microphone access.
19. I CAN HEAR THEM BUT THEY CANNOT HEAR ME
This is called:
one-way audio
Possible causes include:
- NAT
- Firewall
- RTP handling
- Incorrect network configuration
- Codec incompatibility
- Router SIP ALG
Start with the simplest tests:
1. Try another network.
2. Verify microphone permissions.
3. Check the selected audio input device.
4. Review the Zoiper network settings.
5. Only then move into advanced NAT/STUN/RPORT troubleshooting.
Zoiper specifically identifies network/NAT configuration as a common source of one-way or missing audio.
20. THEY CAN HEAR ME BUT I CANNOT HEAR THEM
This is the reverse situation.
Check:
- Speaker volume
- Correct output device
- Bluetooth routing
- Zoiper audio permissions
- Network/NAT configuration
- Firewall behavior
If headphones or Bluetooth are connected, temporarily disconnect them and test again.
Sometimes the SIP connection is working perfectly but the operating system has routed the audio to another device.
21. ACCOUNT KEEPS DISCONNECTING
If the account registers and then repeatedly disappears, investigate the network before rebuilding the account.
Possible causes include:
- Unstable Wi-Fi
- Mobile OS background restrictions
- Battery optimization
- NAT timeout
- Transport configuration
- Multiple devices registering the same account
Zoiper notes that registration and keep-alive behavior can be affected by network/NAT conditions.
On mobile devices, also check whether your operating system is restricting Zoiper from running in the background.
22. MULTIPLE DEVICES
Avoid registering the same SIP account on multiple devices unless you specifically intend to do so and the service configuration supports it.
For troubleshooting, keep things simple:
Device 1 → SIP24 → Zoiper
Once that works, add additional devices if needed.
This makes it much easier to identify where a problem originates.
23. CODECS — DON'T CHANGE THEM RANDOMLY
Codecs determine how voice audio is encoded and transported.
You may see codecs such as:
The correct codec depends on what the SIP infrastructure supports.
If calls already work, there is usually no reason to randomly change codec priorities.
If you are troubleshooting codec negotiation, use the codec requirements supplied by the provider or PBX administrator.
24. REGISTRATION VS CALLING
This distinction is extremely important.
REGISTERED
means Zoiper successfully authenticated against the SIP server.
It does
not automatically prove that every possible call destination, codec, route, or network configuration is working.
You can have:
Registered + cannot place calls
or:
Registered + call connects + no audio
or:
Registered + outgoing calls work + incoming calls fail
These are different problems and should be diagnosed separately.
25. QUICK DIAGNOSTIC TABLE
| Problem | First thing to check |
|---|
| Not registered | Username / password / domain |
| Wrong password error | SIP credentials |
| Registration timeout | Domain / transport / network |
| Call connects, no audio | NAT / firewall / RTP |
| One-way audio | NAT / STUN / RPORT / router |
| Cannot hear anything | Speaker / output device / RTP |
| They cannot hear you | Microphone permissions / RTP |
| DTMF doesn't work | DTMF mode |
| Account randomly unregisters | Network / NAT / background restrictions |
26. THE "START FROM ZERO" METHOD
If you have changed so many settings that you no longer know what is wrong, stop modifying the configuration.
Create a clean SIP account profile.
Use only:
- SIP
- Correct domain
- Correct username
- Correct password
- Provider-specified transport
- Provider-specified encryption
Leave optional settings at their defaults unless SIP24 specifically requires something else.
Then register again.
This is usually much faster than trying to remember every setting that was changed during troubleshooting.
27. WHAT SIP24 SUPPORT CAN CHECK
If you have verified your credentials and followed the configuration guide but the account still does not work, contact SIP24 support with useful information.
Include:
- Your SIP account username
- Device type
- Zoiper platform — Android / iOS / Windows / macOS
- Whether the account registers
- Whether calls connect
- Whether there is audio
- The exact error message, if any
Do not send your SIP password publicly.
Support does not need you to post private credentials on a forum thread.
Also avoid sending a screenshot containing your password.
28. IMPORTANT: SIP CLIENT VS DEVICE SUPPORT
Zoiper is a third-party SIP client.
SIP24 can provide the SIP account information and investigate account/server-side issues, but Zoiper's interface, operating-system permissions, local network, router, Bluetooth configuration, and device-specific behavior can vary considerably.
If the SIP credentials are valid and the server is accepting registration, but your particular phone refuses to provide microphone access, that is a device/application issue rather than a SIP credential issue.
The same applies to:
- Broken microphone permissions
- Bluetooth routing
- Incorrect phone settings
- Firewall rules
- Router configuration
- Operating-system battery restrictions
29. FINAL CHECKLIST
Before opening a support ticket, go through this list:
[ ] SIP account exists
[ ] Account has available balance if required
[ ] Correct SIP username entered
[ ] Correct SIP password entered
[ ] Correct SIP domain entered
[ ] Account type is SIP
[ ] Correct transport selected
[ ] Required encryption configured
[ ] Microphone permission enabled
[ ] Speaker/output permission enabled
[ ] Zoiper account shows registered
[ ] Test call attempted
[ ] Audio tested in both directions
[ ] Another network tested if necessary
[ ] NAT/firewall checked if audio is missing
[ ] DTMF checked if keypad tones do not work
[ ] No unnecessary advanced settings changed
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[https://sip24.cc(https://sip24.cc[/url)]
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