Serena
Make sure your Antenna settings in the Fortec receiver are correct.
For example
Look at
DiSEqC switch and mark which side has the C and KU
coaxials
Let's say 1 is for the C and 2 is for the KU side
In Antenna Settings
Antenna 1
LNBF Type: SINGLE (Click OK on Single and change the LO to 5150)
LNB Power: V/H
DiSEqC: 1
Antenna 2
LNBF Type: SINGLE (Click OK on Single and change the LO to 10750)
LNB Power: V/H
DiSEqC: 2