If like me you run CM12 custom roms you have probably seen this error pop up and read all the articles about clearing caches, uninstalling play store and then realised that none of it worked.
The only fix I’ve seen work is this:
— arter97 (@arter97) May 27, 2015
Download libjavacore.so to your phone. Then open root browser or another root file explorer and rename the file on your phone /system/lib/libjavacore.so to libjavacore.so.old
Then, copy the new file you downloaded to /system/lib/libjavacore.so
Thats it – the annoying error should disappear.
Thanks to @arter97 and @temasek for investigating and posting this fix.