I get a message: system settings changed by another application. The message repeats each time I close it. My email stopped receiving. What is going on?

I get a message: system settings changed by another application. The message repeats each time I close it. My email stopped receiving. What is going on?

Machine Name: iBook G4

Machine Model: PowerBook6,7

CPU Type: PowerPC G4 (1.2)

Number Of CPUs: 1

CPU Speed: 1.33 GHz

L2 Cache (per CPU): 512 KB

Memory: 1 GB

Bus Speed: 133 MHz

Boot ROM Version: 4.9.3f0

Serial Number: 4H*****SE7

Sudden Motion Sensor:

State: Disabled

Version: 1.0

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