Download Charles proxy free trial here
start Charles, start new session, click Help on the top part and click “local ip address”, make note of that IP.
on your Vita connect to your Wifi and click on it to change some settings, go to Advanced settings, scroll down to where it says Address and input the IP address you got from Charles, on Port type 8888, go down and press ok.
Now go back to Vita Settings, system update, update using Wifi, you’ll see something come up on Charles on the left plane, right click on it and “Save All” to desktop.
Go to the file you saved on you desktop and open it with notepad or something like that, scroll to the right and every time it reads “3.00″ just change it to whatever your actual firmware is, example. 2.61. Once you are done with that save the file and exit. Go back to charles.
On the left pane once again right click on the “http://fus01…” and go all the way to the bottom where it says “Map Local” click on it then click on Choose and look for the File you saves earlier to you desktop, click ok.
On the vita go back to settings then press Update and try to update through Wifi, if everything is fine it should tell you, you have the latest Firmware
You should then be able to access the PSN, run the content Manager assistant, etc… good luck