thumbnail not showing in windows 10

Here are two reasons why thumbnail not showing in windows 10 :

1. Check performance option :

• type : “sysdm.cpl” on your cortana or search near windows logo at left bottom corner of screen that will show “system properties” option
• go to “advanced”
• check “show thumbnail instead icons”

• click OK and then apply

2. check file explorer option

• Open the File Explorer.
• Click View tab option.
• Click Options >> change folder and search option to open “folder option”.
• Click on the View tab.
• Make sure to clear the check mark for the Always show icons, never thumbnails option.
• Click Apply.
• Click OK to complete the task.