Hi Odin Ive been trying to fix this issue since the last patch.
Finally I chatted to some friends who also had the problem.

Heres the easy fix...........

Go to http://www.atomicgamer.com/games/3709/navy-field/files
and download the game client for version 1.320

Once downloaded, install as usual and allow it to patch.

Once done click play and you are ready to go.

Seems the prob didnt appear until recently and this version of the client is problem free and It worked for me.
Bare

Perform an MD5 Check to determine if any files are missing or corrupt. You may also consider turning DEP for NF.

MD5 Check:

http://navyfield.com/Community/Forum/View.aspx?num=1989&searchtype=0&pagecount=0&searchvalue=&sort=5&category=E01&page1=1

DEP Instructions:

1.) Open "Control Panel"

2.) Click on "System and Maintenance"

3.) Click on "System"

4.) On the left side click on "Advanced System Settings"

you will be asked for permission to continue, click continue ( It will show up if you
have UAC enabled)

5.) Click on the Advanced tab and then on "Settings" in the Performance area

6.) Click on the DEP (Data Execution Prevention) tab

7.) Put a tick in the little circle next to "Turn on DEP for all programs and services
except those I select" and click on the "ADD" button and browse for and click on
the .exe file for "Navyfield" or
any other App in the NavyField folder then click "Open" now click "Apply" then "OK"

8) close all open windows, Reboot and your done

Phrozen