Ubuntu – Connecting to Windows7 share gives mount error

Hi I am having trouble with Ubuntu 11.10 to the workgroup containing windows computers.

I am getting this message when I click on the workgroup I want to access from the Ubuntu Network interface:

"Unable to mount location  
Failed to retrieve share list from server"

How can I solve this problem?

Output of sudo iptables -L:

Chain INPUT (policy ACCEPT)
target     prot opt source               destination         

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination  

Every time I try to connect to my windows shares using

sudo mount -t cifs //ip_from_windows_pc/sharename /media/winshare -o username=windows_username,password=windows_password_for_user,iocharset=utf8,file_‌​mode=0777,dir_mode=0777

it returns

mount: Cannot allocate memory

I have noticed that on the system event log in Windows I also get this fault every time I try to connect with the Ubuntu computer

The server was unable to allocated from the system nonpaged pool because the server reached the configured limit for nonpaged pool allocations.