Simple key 'encryption'

[vbNeo]

Private Function InvertString(sT As String) As String
Dim sTT As String
 
For I = Len(sT) To 1 Step -1
sTT = sTT & Mid(sT, I, 1)
Next
 
InvertString = sTT
 
End Function
 
Private Function Encrypt(sT As String, sKey As String) As String
Dim sEncrypted As String
Dim keyCount As Integer
 
sT = InvertString(sT)
sKey = InvertString(sKey)
keyCount = 1
For I = 1 To Len(sT)
sEncrypted = sEncrypted & Chr(Asc(Mid(sT, I, 1)) + Mid(sKey, keyCount, 1))
keyCount = keyCount + 1
If keyCount > Len(sKey) Then keyCount = 1
Next
 
Encrypt = sEncrypted
 
End Function
 
Private Function Decrypt(sT As String, sKey As String) As String
Dim sDecrypted As String
Dim keyCount As Integer
 
sKey = InvertString(sKey)
keyCount = 1
 
For I = 1 To Len(sT)
sDecrypted = sDecrypted & Chr(Asc(Mid(sT, I, 1)) - Mid(sKey, keyCount, 1))
keyCount = keyCount + 1
If keyCount > Len(sKey) Then keyCount = 1
Next
 
Decrypt = InvertString(sDecrypted)
 
End Function

Just use, Encrypt() And Decrypt() - remember to pass the same key!!