How can I restore 8.1 on my Lumia 535?

[Windows Central Question]

Problems restoring software Lumia 535

I tried installing Windows 10 on my Lumia 535 phone and it was lagging badly so I wanted to get back to 8.1.
After hard reset it just did a clean install of Windows 10.
Then I tried using Windows device recovery tool to restore Windows 8.1 but whenever I start downloading old version I get the error that the file cannot be downloaded.
How can I restore 8.1 on my phone?

 

[libra89]

You have to enter the insider app, and then remove yourself. How to stop getting Insider builds of Windows 10 Mobile | Windows Central

Then use the recovery tool to roll back to 8.1 : How to roll back from Windows 10 Mobile preview to Windows Phone 8.1 | Windows Central