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In admin mode, you can manually upload certificates in the Unknown Certificates tab. Every attempt to upload a unknown certificate will fail. Please refer to the log and assure your certificate is in DER format and is either signed by one of phone's authorities or server certificates.

Procedure for upgrade firmware

a. Open the Web User Interface of the snom and navigate to the Software Update page.

b. Copy and paste this URL:

http://provisioning.snom.com/download/fw/snom300-8.7.3.19-SIP-f.bin

into the Firmware field and press load

c. The phone reboots and may ask you to perform the update, click ‘Yes’.

After that, the phone is upgraded to version 8.7.3.19.

Basic Configuration of the SNOM 300/320:

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Step 3	Step 4
Insert the "*1*" string in the third column: These DTMF activate the transfer mode.	Act the same way for another dial button (i.e. P4) but this time insert the "*3*" DTMF train: this one activates the "3-way call"

Procedure for upgrade firmware

a. Open the Web User Interface of the snom and navigate to the Software Update page.

b. Copy and paste this URL:

http://provisioning.snom.com/download/fw/snom300-8.7.3.19-SIP-f.bin

into the Firmware field and press load

c. The phone reboots and may ask you to perform the update, click ‘Yes’.

After that, the phone is upgraded to version 8.7.3.19.

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