How to uninstall FileManager on Android?

Go to the list of installed software and uninstall the software.
The best file explorer is ES Explorer.

When you are in the list of device administrators, you don't have time to uncheck because it redirects you elsewhere? WTF!!!

I have the same damned problem, and it's as soon as we let go of the click on the blue icon that it goes back to the page.

It is impossible for me to understand your problem; no application can cause such damage without root rights. And even if your device were rooted (is it? if the warranty is still valid, probably not), it requires your permission (yes/no) before the operation.

So the phone is "bricked" (the result of a bug), which means it needs to be reset. It is indeed the customer service that takes care of it.
As for the data, please note that it is highly recommended to always store it on a micro-SD card.

Ok, thanks!
Half of the data I have on a micro SD, the contacts and photos I have in Avast backup! The apps are on the phone.

Even if the apps were on the µSD card, they would not be operational after a reset. However, the Play Store keeps a list of the apps you were using.

Thank you for your detailed tutorial. The only problem is that in this case it doesn't work. When you select it, it takes you back to the previous screen. If you even want to add an additional administrator, it also takes you back to the previous page.
If my phone were rooted, I would have shown you.

I just tested it: I can easily uninstall a device admin app with Root Uninstaller.

Check the following two details:
- Have root rights
- Have the latest version

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Hello there, I just signed up.
Unfortunately, you didn't grasp the issue at the time you wrote this post.
It's not an application installed by the vendor, it downloads itself when you open certain pages on your smartphone.
"File manager" is just a front to make this app appear harmless,
Administrator means much more than "can't be accidentally deleted," it has access to EVERYTHING, a message clearly informs you that the software can record all your data, manage your connections, modify your settings, it's frightening.

Hello you, the other one,

You can't install an app by accident.
There are two possibilities:

• The ad redirects to the PlayStore
• The ad redirects to the APK

In both cases, user confirmation is required to install the app: the one where Android shows the list of permissions requested by the app about to be installed.
Moreover, if it's the APK, you even have to go into the settings to allow unknown sources.

In short: from my point of view, you have to be stupid to accept the unsolicited installation of an app you don't know.

I didn't expect that at all...

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