Windows 7 Professional (64-bit) + Service Pack 1
CCleaner 5.15.5513 (64-bit)
Chrome 48.0.2564.116 m (32-bit)
CCleaner 5.15.5513 does not properly clean Google Chrome's history. Steps to reproduce:
1) Open Google Chrome, and go to "chrome://history/".
2) Click "Clear browsing data and check every option along with selecting "from the beginning of time".
3) Now that you've successfully cleared the history from within Google Chrome, navigate to a single website (e.g., www.piriform.com).
4) Once https://www.piriform.com is completely loaded (to establish this in history), close out of Google Chrome.
5) Run CCleaner 5.15.5513 with the option for clearning Google Chrome's history checked.
6) After running CCleaner successfuly DO NOT OPEN Google Chrome (yet).
7) Open up the following file in a hex editor (or text editor) "%LocalAppData%\Google\Chrome\User Data\Default\History" (SQLite database file)
8) Search for "piriform" and you'll find traces of that string and url we tested to establish some history.
9) Close the History file in the hex editor (or text editor) and open up Google Chrome.
10) Navigate to "chrome://history/" and it'll say you have no history, however, traces of your history will forever be collected in "%LocalAppData%\Google\Chrome\User Data\Default\History" which is very misleading.
The only way to ensure your Google Chrome's history is properly cleaned is to add "%LocalAppData%\Google\Chrome\User Data\Default\History" to file inclusions to be cleaned within CCleaner.