E-mail woes

For a number of weeks 95% of mom’s outbound e-mail bounced back to her saying there were viruses attached to her messages. Her local ISP told her it was the fault of their contracted outgoing message handlers. She, naturally, found this Very frustrating. Suddenly I started getting e-mail from her again four days ago. The fix, evidently, had to do with her mouse, which she discovered had one leaking, gooy corroded battery, one good battery, but still, somehow showed an arrow on her screen! She said she cleaned the battery case with denatured alcohol, put two new batteries in, and e-mail started flowing again. I wish all fixes were so easy.