Wine doesn't run normally anymore. Need to run wineserver before every command now

After installing playonlinux to test one of its scripts, running wine on any Windows executable or even winecfg does nothing. Running winetricks outputs:

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wine cmd.exe /c echo '%ProgramFiles%' returned empty string
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Searching that output online led to solutions that say to not run Wine as root, or to change ownership of the Wineprefix folder to the current user. That didn't help because I don't run Wine as root anyway and the ~/.wine folder and everything in it belongs to me.

I haven't even run any application yet with playonlinux, but uninstalling it and even reinstalling everything Wine-related doesn't fix the problem (I use the ubuntu-wine ppa).

However, after accidentally using tab complete on the wrong thing, I learned that running wineserver before anything Wine-related makes it run as it normally would.

What did playonlinux do on install that possibly caused Wine to not run normally?

Edit (2015/08/02) It wasn't playonlinux. It was a kernel problem. I mistakenly assumed it was the former because it was the only Wine-related package I marked for installation at the same time that I also upgraded to the problematic kernel version. See link in answer below for more details.