Android Studio: app with same package but different signature is already installed?

Question

Java

I can’t install the application on the device via usb, the studio writes that the application is already installed, and the update is not possible due to package incompatibility. At the same time, I deleted the previous version from the device.
Before that, I worked on Ubuntu and, accordingly, the project was built there, such an error appeared after compiling the same project on Win 10. But as I understand it, this is not the problem, since the same project was compiled on Win 10 and installed via usb without any problems from another person.
I repeat - this application is not on the device, but the studio says it is. What could be the problem and how to solve it? Many thanks for the advice.

Answer 1

with a high probability, you have not completely deleted the application from the device.
The reason for the error is that different keystores are used in win10 and ubunt (this is a debug of keystores, which the studio generates itself, but they are unique) to sign one apk.