From the command line:
enable
[enter password]
config t
interface pri 1
no shutdown
[Ctrl-Z]
write memory
From the GUI:
Physical Interfaces on left-hand menu
Locate the E1 physical interface in the list.
Click on pri 1 under its logical interface column.
Check the Enabled box.
Click the Save button.
From the command line:
enable
[enter password]
config t
interface pri 1
no shutdown
[Ctrl-Z]
write memory
From the GUI:
Physical Interfaces on left-hand menu
Locate the E1 physical interface in the list.
Click on pri 1 under its logical interface column.
Check the Enabled box.
Click the Save button.