[Lua][Error]Attempt to index? (a null value)

Ok, So I have been working on an A.T.M for our server bank, but keep on getting the same error, and I don't understand it

code: http://pastebin.com/jNg6PZrK

EDIT: The error is on line 41, and updated code to latest version

Please get back to me soon, thanks in advance, dvd604

Ps, Who ever figures this outis a genius :P/>/>

I need help, I'm stumped :P/>/>

Try to change line 41 too:

file1.close()

Allso change line 51 too

file.close()

Allso there is no need to bumb a post.

Ok, I changed some of the code and added comments on the errors:

--Global Vars
local version = "0.1 Beta (Broken)"

--Startup code for directory

if fs.exists("/bank/") then
  print("Bank Directory exsits, skipping Create code!")
else
  fs.makeDir("/bank")
end
sleep(2)

--end

--Money declorations
local money = "0"
local account_money = money
--end

--main loop
while true do
  if money ~= "0" then
    account_money = money
    money = "0"
  end
  term.clear()
  term.setCursorPos(1,1)
  print("Money Server ", version)
  print("")
  print("Please note, this is monitored 24/7")
  write("Account name: ")
  local account = read()
  if fs.exists(fs.combine("bank/", account)) then
    local file = fs.open(fs.combine("bank/", account), "w") -- open file in write mode
    file.writeLine("1000") -- write "1000" to the file
    if file.readLine() ~= "" then -- read a line from file. ERROR: file is in write mode, you can't read
	  account_money1 = file1.readLine() -- read another line from the file. Same error here
    end
  end
  file.close() -- close the file
  print(account.." contains $"..account_money1)
  write("Edit? ")
  local ans = read()
  if ans == "yes" then
    write("Amount to withdraw: ")
    money = money - read() -- ERROR: trying to subtract two strings
    local file = fs.open(fs.combine("bank/", account), "w")
    file.writeLine(money)
    file.close()
  end
end

The main problem is the file handling. Try learning how the fs api works to solve this.

Thanks very much to both of you, and sorry for the bump. I will get back to you if it fixes it :P/>/>