This page provides detailed information about the hardware and software requirements for your computer to be able to send and receive SMS messages using the Ozeki NG - SMS Gateway software.

To run the Ozeki NG - SMS Gateway software on your computer, you have to meet some essential hardware and software requirements.

Hardware requirements

In all cases better hardware gives you better performance. The most important factor regarding performance is the amount of RAM in you computer, and the speed of your hard disk.

  • CPU: 4 cores
  • RAM: 4 GB (16 GB recommended)
  • Hard disk space: 4 GB (SSD recommended)
  • Ports: RS232 or USB (if you use a GSM modem)
  • Phone-to-PC data cable (USB or RS232) or
  • Network: Internet connection (if you use IP SMS connection)

Virtual hardware

Ozeki NG SMS Gateway is also optimized to run in virtualized environments. Microsoft, VmWare, Linux KVM, Oracle and many other virtualization platforms are supported.

GSM modem

If you wish to use a GSM modem attached to the PC with a phone-to-PC data cable for SMS messaging, you need a suitable device. For more information about suitable telephones for SMS messaging, check out the Recommended SMS Hardware guide.

Software requirements

Ozeki NG - SMS Gateway runs on one of the following operating systems:

  • Windows 11
  • Windows 10
  • Windows 7
  • Windows 8

  • Windows Server 2022
  • Windows Server 2019
  • Windows Server 2016
  • Windows Server 2012 R2

The following updates should be installed:

  • .NET Framework 4.0

You can download Ozeki NG - SMS Gateway and the programs listed in the software requirements on the Download SMS Gateway page ( You should always download and use the latest version of Ozeki NG.


When I try to submit a message, I receive an error. What can be the reason?

If you experience occasional delivery failures, the issue could be a temporary network glitch. Ozeki NG allows you to configure automatic message resending for increased reliability.

How to Configure Resending:

  1. Open the "Edit/Server preferences" menu.
  2. Click on the "Advanced" tab.
  3. Locate the "Max number of tries:" field.
  4. Increase the default value to allow for additional attempts (e.g., 2 or 3 tries).

By increasing the retry limit, you give your message a higher chance of success if the initial network connection is unstable.

However, if messages consistently fail to submit, the problem lies elsewhere. Here are some potential reasons:

  • Insufficient SIM Card Balance: Ensure your SIM card has enough credit to cover SMS sending costs.
  • Incorrect SMSC Configuration: Double-check your SMSC configuration settings within Ozeki NG to ensure accuracy.
  • Active SIM PIN: If your SIM card requires a PIN for use, make sure it's disabled to avoid blocking communication.

For a comprehensive list of potential reasons behind message submission errors, please refer to the following webpage: SMS submit error reasons

I can send SMS, but I cannot receive with my modem. Why?

While you might be using a standard mobile phone to connect to Ozeki NG SMS Gateway, it's not the ideal solution for reliable incoming message reception. Here's why:

Most standard handsets come with built-in software designed to manage incoming SMS messages for the phone user. This software often stores and displays messages on the phone itself, but here's the catch:

  • Message Interception: This internal software might intercept incoming SMS messages before they reach the data cable connection to your PC. This prevents Ozeki NG, running on your PC, from receiving the messages.

If your phone uses the Symbian operating system (common in older high-end Nokia and Sony Ericsson devices), it's particularly unsuitable:

  • Symbian Limitation: These phones are known for not delivering incoming SMS or delivery reports through the modem interface, making them incompatible with Ozeki NG for receiving messages.

For reliable incoming SMS reception, we strongly recommend using a dedicated GSM modem instead of a standard phone. Here's why:

  • Our Website's Guidance: As you noticed, our recommended devices list on Recommended GSM devices for SMS messaging only includes GSM modems.
  • Industrial-Grade Reliability: We suggest models like Siemens TC65 or Wavecom Fastrack. These industrial GSM modems are known for their stability and reliability, perfect for building professional, dependable SMS applications.
  • GSM 7.5.0 Support: If you choose another model, ensure it supports the GSM 7.5.0 SMS standard for compatibility.
By switching to a dedicated GSM modem, you can ensure consistent and reliable incoming SMS reception within Ozeki NG SMS Gateway.

Does Ozeki NG SMS Gateway handle a modem with multiple sim cards?

While Ozeki NG SMS Gateway doesn't directly support modems with multiple SIM cards, you can still achieve this functionality by connecting multiple individual GSM modems to your system.

This setup allows you to leverage the capabilities of several SIM cards, potentially:

  • Increased Capacity: Send and receive a higher volume of SMS messages simultaneously.
  • Separate Lines: Utilize different phone numbers for various applications or user groups.
  • Redundancy: If one modem encounters an issue, others can continue operating, minimizing downtime.

You have two convenient options for connecting your GSM modems:

  • USB Ports: This is a widely used and user-friendly method for modern computers. Simply plug the modem into a free USB port.
  • RS232 Ports: This older but reliable serial communication method offers a stable connection for specific modem models.

By connecting multiple GSM modems, you can significantly enhance your SMS capabilities within Ozeki NG SMS Gateway. Remember to ensure your system has sufficient resources to handle the combined load of multiple modems for optimal performance.

I can send, but I cannot receive SMS messages. What can be the problem?

Ozeki NG relies on inbound routing rules to determine where to send incoming SMS messages. These rules act like instructions, directing messages to specific destinations.

Check the Inbound routing settings:

If my Android device supports two (2) sim cards - can I receive SMS messages on both of the SIM cards? Which of the sim cards is the one, that will send the SMS message to a mobile phone?

The Ozeki Android SMPP SMS Gateway acts as a bridge between your Android phone and the Ozeki NG SMS Gateway software on your computer. Here's how they work in tandem:

  • Incoming Messages: Any SMS message received on any SIM card in your Android phone is forwarded to the Ozeki NG SMS Gateway. This ensures all incoming messages, regardless of the SIM card used, are captured by the central software.
  • Outgoing Messages: When you send an SMS message from your phone, the Ozeki Android app is not directly involved. The message is routed through your phone's default messaging app and sent to the recipient using the SIM card currently active on your phone (the one with cellular data or voice service active). This maintains the standard sending behavior of your phone.
In essence, the Ozeki Android app acts as a receiver for incoming messages on all SIM cards, while your phone's default messaging app handles outgoing messages based on the active SIM card.

Can I use my smart phone as a GSM modem?

While directly using a smartphone as a traditional GSM modem isn't typically possible due to software limitations, there are workarounds for connecting your phone to Ozeki NG SMS Gateway.

Can I use my micro SIM card with Sierra Wireless Fasttrack modem?

Yes, you can use a micro SIM card with a Sierra Wireless Fasttrack modem! Here's what you'll need:

  • SIM Card Adapter: Purchase an adapter that converts your micro SIM card to a standard mini-SIM (2FF) size. This allows it to fit physically into the modem's SIM card slot.
The Ozeki NG SMS Gateway software paired with the Ozeki Android SMPP SMS Gateway app provides a powerful solution for managing SMS traffic on your computer, even if you can't directly use your smartphone as a traditional modem.

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