VS 2010 - Dropdownlist Getting Index

I've made a small site which purpose is to allow people to add members to their clan. The page has a dropdown list with the names of all available clans.

The name of the clans and the clan password come from a text file which is read when loading the page (but not when there's a page postback) and adds the clans to the dropdownlist.

The clan name and clan password are also read into an array for later use.

When the user selects an item in the dropdownlist I want to get the index so I know which clan name to use and which password.

I tried getting the index by using the indexchanged event and also just the click event of a button but somehow this doesn't seem to be working properly.

When the user filled in all fields and hits the submit button I want to check if the password is correct and want to know the clanname. I'm trying to do this by using the array's with that data and setting the item of the array equal to the index of the selected item in the dropdownlist.

But when I press the button I keep getting a wrong password error even though it's correct. If I remove the password check and submit it then the form should create or append to a text file with the name of the clan. But when submitted the text files is .txt instead of clanname.txt.

Tried setting the dropdown to autopost back or without and get the same result.

My code is the following:

reading the data into the array + adding the clannames to the dropdownlist

vb Code:
Dim data() As String    Dim clanname(50) As String   
Dim clanpass(50) As String Protected Sub Page_Load(sender As Object, e As System.EventArgs)
Handles Me.Load        
Dim fileName As String = "C:/ClientSites/data/clans.txt"       

[Code] ....

The submit button code

vb Code:
Protected Sub btnSubmit_Click(sender As Object, e As System.EventArgs) Handles btnSubmit.Click        
naam = txtMemberName.Text.ToString        gamertag = txtGamerTag.Text.ToString       
platform = txtPlatform.Text.ToString         index = DropDownList1.SelectedIndex        
paswoord = clanpass(index)                    

[Code] ....

In short I load in data from a file into two arrays, clanpass and clanname. Populate the dropdown with the clannames. Then upon submitting I want to check the password against the password for the selected item by using it's index. I also want the name to write it to the correct text file.