UIForETW silently exits if it cannot retrieve "My Documents" path

[TautvydasZilys]

Relevant code:

UIforETW/UIforETW/UIforETWDlg.cpp

Line 581 in f916345

const BOOL getMyDocsResult = SHGetSpecialFolderPath(*this, documents, CSIDL_MYDOCUMENTS, TRUE);

I was trying out UIForETW on my home machine after a recent boot and have not bitlocker unlocked all of my drives. My documents folder was under one such locked drive. I realize it is my fault for this, but at the very least UIForETW could have told me so, as I had to install a debugger just to figure out what's going on.

By the way: the same happens to WPRUI.exe :).

[randomascii]

Adding better error handling would be nice - a message box and then exit. This isn't a priority for me but if you want to create a PR I'd be happy to accept it.