[Serusers] Error: sorry --cannot open write fifo

Hello

I continue with my test of SER. SER is running almost OK, but I have some problems. Sorry if this is a newbie question, but is really important to me configure SER correctly.

When I try to enter to serweb user_interface, I have this error:

sorry --cannot open write fifo

I can add, delete contacts with serweb, but I can't send Instant Messages(nor whit Windows Messenger). I have read fifo is the communication way between ser and serweb, and responsible for instant messages.

In config.php, the configuration is $this->fifo_server="/tmp/ser_fifo" And in ser.cfg the configuration is fifo="/tmp/ser_fifo"

I think is OK, isn't it?

What can be wrong?

One more time, thank you very much for your time an knowledge.

Curro