Function stopping at if statement?

I am making an auto updater for my OS, and i got stuck. It checks to see if the OS version is not the version of the OS that is on pastebin, by downloading a separate pastebin file called version. Then it checks if you want to update, and if so, it updates. It IS downloading the version file, this i KNOW is happening, but why is it not working? it should run, because A0.20 and A0.15 are NOT the same.

Here is my code:

local version = "A0.15";
function pastebinGet(code,path)
local sPath = shell.resolve(path);
local response = http.get("http://pastebin.com/raw.php?i="..textutils.urlEncode(code));
if response then
local contents = response.readAll();
response.close();
local file = fs.open(sPath,"w");
file.writeLine(contents);
file.close();
return true;
else
return false;
end
end

function update()
pastebinGet("jh1xgkC5","/.winMC/.OS/version");
verr = fs.open("/.winMC/.OS/version","r");
vers = verr.readLine();
verr.close();
print(vers);  --THIS WORKS, JUST FYI SO IT IS DOWNLOADING THE VERSION, BUT WHY IS IT NOT CHECKING THE VERSION? ("A0.20", which is OBVIOUSLY not the same as "A0.15")
if not version == vers then
  screenClear(); --FYI THIS IS S FUNCTION, JUST NOT SHOWN IN THE CODE HERE! AND IT WORKS!
  term.setCursorPos("1,1");
  col("colors.green"); --THIS IS A FUNCTION TOO, JUST NOT SHOWN. IT IS: local col = term.setTextColor;
  print("AN UPDATE IS AVAILABLE, WOULD YOU LIKE TO UPDATE NOW? (YES/NO)");
  local yn = string.lower(read());
  if yn == "yes" then
   print("Downloading update data...");
   if not pastebinGet("gMPNTcBe","/.winMC/.OS/update") then
	col(colors.red);
	error("An error occured while updating Windows MC");
   end
   print("Installing");
   fs.delete("winMC");
   fs.move("/.winMC/.OS/update",winMC);
   print("UPDATED SUCESSFULLY, REBOOTING");
   shell.run("winMC");
  else
   print("Okay");
  end
end
end

update();

Try to avoid stating what a program doesn't do. That isn't useful information. Concentrate on being clear about what it does do instead.

(Eg, saying "when I compare the versions my condition is always treated as false" is a lot more descriptive then saying "my program doesn't work".)

Anyway, replace "if not version == vers then" with "if version ~= vers then".