Upgrading the DECT M700 and handsets may require using the TFTP method firmware version older than v3.24 or if you have Network policies that restrict your Internet access.


The current release of firmware for the M700 Base and the M65 Handset is v355B21. The current upgrade process, as indicated on the Snom Website and the current documentation, does not appear to work in your environment when you try to upgrade via the Internet.


The M700 and handsets can be upgraded manually using TFTP.


Upgrading base or handsets from version 324 or earlier:

  • IMPORTANT NOTE 1: After upgrading to the version 355BXX you WILL NOT ABLE TO DOWNGRADE TO THE VERSION 324BXX. Please take this upgrade carefully
  • IMPORTANT NOTE 2: The upgrade will remove all the manually uploaded contacts from the global addressbook. Please make sure to re-upload the addressbook after the update. The old and new firmware binaries for download can be found under:
  • IMPORTANT NOTE 3: In case you are doing the update from a 323 version you need to update to the version 324B12 before applying the version 355
  • You can find the latest available release here


1. Download the Snom SPLiT application

2. Run the TFTP server

On Windows:

run the SPLiT executable as Administrator

On Mac/OSX:

Open a terminal

add the execution permission to the SPLiT Application: chmod +x SPLiT_1.1.1_OSX

run the SPLiT executable in a terminal using sudo: sudo ./SPLiT_1.1.1_OSX

Once the software is started:

Click on the Debug check box

Insert your computer IP address into the IP Address field

Verify that the TFTP Directory fields contains the tftp value

Click on the Start TFTP Server button

3. Save the SPLiT software into a directory, in the same directory create a subfolder named tftp (lowercase).

4. Create (3) New Folders in the TFTP Directory. Name one M700, M85 and the other M65. Be sure to use the capital letter M.  Next, download the latest firmware from the Snom Website to the TFTP directory.

Firmware binaries needed for upgrade from V324xx to V355B21






Firmware binaries needed for upgrade from V323xx to V324B12






5. Once the files are downloaded, copy the M700_v0355.fwu to the M700 folder, M85/M85_v0355.fwu to the M85 forlder and the M65_v0355.fwu to the M65 folder.

6. To prevent a permissions issue when the M700 tries to access the .fwu files, right click on the TFTP folder, chose ‘Share With > Specific People’, choose ‘Everyone’ from the drop down and then Add. One added give Everyone Read&Write access to the files and then click Share.

Upgrading the M700 Base and Handsets

7. Login to the M700 (Chose the Primary M700 if this is a Multi Cell configuration)

8. Navigate to the ‘Firmware Update’ settings.

9. Determine the IP address of your Computer that is running the SPLiT TFTP Server and enter the IP address in the ‘Firmware update server address:’ field.

10. Leave ‘Firmware Path’ blank, type 355 in the M85 and M65 type field, Build version is 21

11. Make sure the M85s and M65 Handsets are registered to the M700 Base.

12. Place the M85s M65s in there charging cradle to start the upgrade process.

13. Click ‘Update Start’ and then confirm the upgrade when prompted by clicking OK.

14. You can monitor the M65s upgrade progress from the ‘Extension’ page of the M700

15. The M65s could take up to an hour to upgrade based on the Network utilization and traffic.

16. Once the phone has upgraded, as indicated by the ‘Extensions’ settings page, confirm the version on the phone by going to Menu > Status and checking the SW version is 355