Some Android devices, if you can not access you might try this:
while holding the power on button
press the up volume or down volume and many times you can access the default settings
which will allow you do Factory Reset - some times you can do a soft reset
another was remove the battery for 3 min (never tested this).
but I find the best is to do a backup of all your stuff the the added SD Card. you also can backup to your computer this way.
then if needed reapply the data back to the added SD Card, which would (should make it clean) then do a restore
From the Phone's Storage:
- Open the apps drawer and launch "My Files"
- Tap "All files" > "SD card"
- Press "Menu" and tap "Select"
- Check the box(es) associated with the items you wish to restore
- Press "Menu" and tap "Move" > "Device storage"
- Access the location where you want to restore the files
- Tap "move here" or alternatively, tap "Create folder" or the folder name to restore the files in a different location -------------------
Restore Media Files from a Windows PC:
- Connect the Android Device to the computer via USB
- Drag the "Status" bar down and tap "Connected as a media device"
- Check the "Media device (MTP)" box
- In the AutoPlay window on the computer, click "Open device to view files"
- Open a second Windows Explorer window and locate the backed up media files on your computer
- Copy the desired files and transfer them to the smartphone in the "Card" or "Phone" (sub)directories
- Once the transfer is complete, click the "mass storage device" icon from the system tray and disconnect your smartphone