Fax not working

[RDWild]

Hosted 3cx, Grandstream HT801. Incoming faxes ring, the fax machine picks up, fax never received. If you call it from a regular phone, fax picks up and you hear fax tones. What could be wrong?

 

[TheodorosG_3CX]

Note that Gateways are not supported, for those issues you should contact your provider first.

 

[RDWild]

It's right there on the supported ip phones page....
https://www.3cx.com/sip-phones/

 

[SweetAction]

Fax over VOIP is always a massive pain.
You will need to do some playing around. Some areas to look at:
1. You need to make sure that the ATA is set with the correct codecs (T.38 or G711 as needed). You need to check what your Trunk supports and configure the ATA to match
2. You need to look on the fax machine itself for IP Faxing settings. For example, on Brother units there is a setting called oversea mode that can help. Also looking for ECM support.
Good luck. I suggest either an efax provider or an actual pots line direct to the machine if you want an easy time of it.

 

[TheodorosG_3CX]

The steps provided from @SweetAction are the correct. Note that we do not provide support for Gateways as it is also mentioned in our Support Procedures.

 

[colonial]

I use grandstream handytone ATA's a service called t38fax.com its fantastic

 

[SweetAction]

I use grandstream handytone ATA's a service called t38fax.com its fantastic

Can confirm, we use them as well in some cases, they work well.