[BumbleBernie]

Here is the log:
--------------------
calibre Debug log
calibre 1.28 [64bit] isfrozen: True is64bit: True
Windows-7-6.1.7601-SP1 Windows ('64bit', 'WindowsPE')
('Windows', '7', '6.1.7601')
Python 2.7.5
Windows: ('7', '6.1.7601', 'SP1', 'Multiprocessor Free')
Starting up...
Started up in 17.13 seconds with 1431 books
SMART_DEV ( 0.12: 0.125) _attach_to_port try ip address "" on port 9091
SMART_DEV ( 1.08: 0.827) startup_on_demand listening on port 9091
SMART_DEV ( 1.19: 0.047) _attach_to_port try ip address "" on port 54982
SMART_DEV ( 1.25: 0.000) startup_on_demand broadcast socket listening on port 54982
SMART_DEV ( 2.34: 1.029) run All IP addresses {'{846EE342-7039-11DE-9D20-806E6F6E6963}': [{'broadcast': '127.255.255.255', 'netmask': '255.0.0.0', 'addr': '127.0.0.1'}], '{161D3BC3-6121-4E1F-BD75-E40CFFE09088}': [{'addr': '169.254.143.203'}], '{0321AD0D-F905-447F-8FF8-6CE6AE12CD93}': [{'broadcast': '192.168.11.255', 'netmask': '255.255.255.0', 'addr': '192.168.11.4'}]}
-------------------------------------------

I did notice that port 8080 does not show up, but the port for wireless device connection 9091 (which I set instead of 9090). According to a responce from Steve, Calibre Companion) this should make no difference.

I now set to port to 9090 and suddenly the local access via Firefox worked.
Here is the log:
-------------------
calibre Debug log
calibre 1.28 [64bit] isfrozen: True is64bit: True
Windows-7-6.1.7601-SP1 Windows ('64bit', 'WindowsPE')
('Windows', '7', '6.1.7601')
Python 2.7.5
Windows: ('7', '6.1.7601', 'SP1', 'Multiprocessor Free')
Starting up...
Started up in 14.44 seconds with 1431 books
SMART_DEV ( 0.02: 0.016) _attach_to_port try ip address "" on port 9090
SMART_DEV ( 1.00: 0.873) startup_on_demand listening on port 9090
SMART_DEV ( 1.09: 0.031) _attach_to_port try ip address "" on port 54982
SMART_DEV ( 1.17: 0.000) startup_on_demand broadcast socket listening on port 54982
SMART_DEV ( 2.25: 1.029) run All IP addresses {'{846EE342-7039-11DE-9D20-806E6F6E6963}': [{'broadcast': '127.255.255.255', 'netmask': '255.0.0.0', 'addr': '127.0.0.1'}], '{161D3BC3-6121-4E1F-BD75-E40CFFE09088}': [{'addr': '169.254.143.203'}], '{0321AD0D-F905-447F-8FF8-6CE6AE12CD93}': [{'broadcast': '192.168.11.255', 'netmask': '255.255.255.0', 'addr': '192.168.11.4'}]}
-------------------------------------

Why is the wireless port selected causing this being unable to connect to the server on 8080?

I am puzzled. I did try this now 3 times 9090 wireless works, 9091 wireless fails.

Addition:
The 3 times I did not restart Calibre.
After restarting it using 9090 - no error.
Changing to 9091 again and restarting Calibre - no error.

Still puzzled - but it works now.

Thanks for all the help !