it’s like two edge knife at one edge it helps to protect your files and at other edge some michivious virus disable your “Show Hidden Files and Folders” options which you can’t able to enable no matter what you do and your protected files  remain protected even from yourself. 

Here is simple three solutions

1st Back Up Your Registry before editing, just in case….

Solution 1   - 

Click Start => Run type in Regedit press OK.

Click:

• HKEY_CURRENT_USER
• Software
• Microsoft
• Windows
• CurrentVersion
• Explorer
• Advanced
• Hidden

In the right hand area, double click hidden and change the value to 1.

Exit Regedit

Now try changing Show hidden files and folders in Tools => Options.

Solution 2

Click Start => Run type in Regedit press OK.

Click:

• HKey_Local_Machine
• Software
• Microsoft
• Windows
• CurrentVersion
• Explorer
• Advanced
• Folder
• Hidden
• SHOWALL

Now right click on CheckedValue and click Delete.

Right click and hover over New then select Dword Value call it CheckedValue.

Right click on CheckedValue and choose Modify, under ‘Value Data’ type in 1.

Exit Regedit

Restart your computer.

Now try changing Show hidden files and folders in Tools => Options.

Solution 3

If nothing works then download Smart Virus Remover by Technize from here:

  Smart Virus Remover 

it’ll restore your Windows settings and your show hidden files and folders will be set to default.

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