What *is* a Logger?

[WindWagonSmith]

This explanation is far from adequate or even on point:

"36. What is the Logger tab and what does it do?

You can log to a file by right clicking -> Log to file. Be sure to specify the FULL SAVE PATH, including the filename. This will not save the buffer, only lines that showed up after you set it. To stop logging, go back to Log to file and hit OK with nothing written in the box."

So...

What is the 'Logger' tab and what does it do?

Why is it saying HASH CHECK FAILED so often?

Is that bad?

[Lord Alderaan]

It is a tab where one can keep an eye on background activities and/or errors. This is useful when tracking down problems and/or trying specific stuff in µtorrent.

Hash Check failed errors are normal when they happen from time to time and can be safely ignored.

[Switeck]

There are groups that use 1000's of hostile peers/seeds to poison torrents. Most of their peers/seeds are in a narrow ip range and use Azureus. uTorrent's ipfilter.dat can be used to block them, vastly reducing hash fail errors...if that's why you're getting those errors.