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1. **How can I cancel “call transfer” or “conference”?**

Canceling these two functions is easy. Simply press the “transfer” button or the “conference” button again. This will end the function.

2. **How do I enable the Syslog feature on my unit?**

If your unit has the Syslog feature (usually found under Advanced Settings), you can use it to troubleshoot any issues. There are two fields for Syslog:

– Syslog Server: Enter the IP address of your Syslog server. If you don’t have one, you can use a broadcast IP address (e.g., 192.168.1.255) and then capture logs on a PC on the same LAN.
– Syslog Level: You can set different levels. For debugging purposes, set it to DEBUG.

3. **How do I enter letters for the MAC address for Factory Reset?**

Coding is based on the alphabetical representation on a regular phone keypad.

For instance, the number 2 key has ABC on it. So, to code B, you need to press 22 where 2 represents itself, 22 represents A, and 222 represents B.

4. **How do I perform a Factory Reset?**

Please unplug all Ethernet cables, keep the power and the phone connected to the Grandstream device.

For HandyTone series models:
– Press *** and listen to the voice prompt.
– Press 99.
– Now, enter the MAC address with the correct coding for alphabets. For example, a=22, b=222, d=33, etc.

For BudgeTone series models:
– Press the MENU button.
– Scroll down to RESET.
– Enter the MAC address with numbers and letters exactly as shown on the LCD screen.
– When you see your full MAC address on the LCD, press the MENU button.

5. **How do I resolve a symmetric NAT router issue?**

Generally, a symmetric NAT issue can’t be solved using STUN detection mechanisms supported by Grandstream products. It can be resolved through a media proxy server provided by your VoIP service provider. Consult your VoIP provider for this information and configure the “outbound proxy” setting on your Grandstream device accordingly.

6. **Why can I make outgoing calls but not receive incoming calls?**

The issue is likely due to intermediate devices such as routers or firewalls blocking UDP ports used for SIP. Ensure that your router or firewall has open ports like 5060, 5004 for SIP, RTP, etc.

7. **What are the supported bit rates for T.38 fax?**

Our devices support the following maximum negotiable bit rates for the T.38 protocol:
– HT5XX/GXW400X/GXW410X/GXE: 14400
– HT4XX: 9600

8. **Why can’t I access the Advanced Settings web page?**

To access Advanced Settings and other Account settings pages, you need to enter ‘admin’ as the password. The default password is usually ‘admin’.

9. **Why can’t I perform a Factory Reset?**

There could be three reasons you can’t perform a Factory Reset:
– You might be entering the wrong MAC address. For HT products, remember to input the MAC as numbers with the correct coding, and for BT or GXP phones, input the full MAC address with letters and numbers.
– If your Internet Service Provider provided the device, they might have locked it with specific settings, preventing a Factory Reset.
– The Dial Plan Update via Web setting might be set to “Yes,” in which case, Factory Reset won’t initiate.

10. **Why can’t I access my Voicemail account?**

Make sure you’ve correctly entered your Voicemail account number in the Voicemail User ID field. Check your DTMF settings as well.

11. **Why can’t my device obtain an IP address?**

Check the connection speed (10Mbps or 100Mbps) of your Internet source (router, modem, etc.). Most Handytone series products and BudgeTone 101 and 102 support only 10Mbps Ethernet connections.

12. **Why is my phone’s LCD screen displaying a random date?**

The issue might be that the phone isn’t receiving a response from the NTP server. Check your network connection and DNS server.

13. **Why can’t my device register to the SIP server?**

Sometimes a user might receive a “403 Forbidden” response indicating incorrect credentials. Simply reentering SIP credentials usually resolves this issue.

Another situation is the device continuously sending registration requests without ever receiving a response from the SIP server. A user can verify if the server is receiving registration requests with the help of the ITSP. If the server receives the request, it sends a “407 Proxy Authentication Required” message to the device. After receiving this message, the device sends another registration request to the server with the appropriate credentials. Sometimes, there are instances where the server sends “407 Proxy Authentication Required,” but it doesn’t reach the endpoint. To address this issue:

– Disable “SIP ALG” in your router if applicable.
– If “SIP ALG” is present and can’t be turned off, it’s recommended to update the router’s firmware to the latest version.

14. **Why does my phone keep ringing on its own, and I hear no sound when I answer the call?**

VoIP phones or ATAs can be easily susceptible to unauthorized access or spam calls. Grandstream has developed protection against such incidents. This protection rejects any call not coming from a legal proxy. This setting needs to be enabled by the user.

15. **Why does my phone display the date as “1900-01-02”?**

This is likely due to either DNS not resolving the NTP server correctly or the NTP server not responding, resulting in the default date “1900-01-02” being shown.

Please note that some technical terms and steps might slightly vary based on the specific device models or firmware versions. Always refer to the official user manual or support documentation for accurate information tailored to your device.