Dennis Verspuij

Hi, yes I tried toggling the SkipUAC checkbox with intermediate restarts, but didn't help. I think indeed the lc.dat is some encrypted database of scan results. Thanks for your time and flagging this issue up, I'll await a next version that hopefully fixes this!

I think I found the culprit. The problem happens because I start CCleaner from the Open CCleaner... context menu item of the Recycle Bin icon on my desktop. In that case the working directory is probably implicitly set to my Desktop folder. Instead the CCleaner start menu shorcut has explicit working directory C:\Program Files\CCleaner, if I start using this shortcut the lc.dat in updated in that installation folder as it should. The mysterious recycle bin invocation parameter /FRB does not seem to have any influence in this. So conclusion CCleaner writes the lc.dat into the working directory instead of installation folder. Or there is something wrong with permissions/UAC and the working directory is used as fallback, because I notice that whether or not I check the Options > Advanced > Skip UAC Account Control warning I will get the UAC prompt nonetheless. I am running latest Windows 11 Pro and do have the CCleanerSkipUAC - myusename task which I think it is supposed to be using to skip the UAC prompt. Finally I am still wondering what the lc.dat is, is it a results database of scanning software updates, or a license file, and if so, why is it updated everytime, and why isn;t it stored in user appdata?

Hi, thanks for your answer. I doubt is is another program writing the file, I can delete the file, run CCcleaner, let it scan for software updates, close it, and then the file reappears, reproducable every time. But your comment got me thinking, I searched the whole filesystem for another lc.dat and found exactly one in C:\Program Files\CCleaner folder, dated somewhere around install time. On other systems I also see this file in that folder, and it being updated after each scan for software updates. So it looks like CCleaner is updating that file upon each scan (is it a database?), but that it mistakingly writes it to my desktop instead of the program folder?

Hi, sorry, replied the wrong route indeed... I was not updating any software, only scanning for software updates!

Hi, when I close CCcleaner64 after letting it check for software updates a file named lc.dat appears on my Windows 11 desktop, see attached example. If have to add read access to myself before I can even open it, the contents are unreadable binary and not recognized by any heuristics file type detection service, nor recognized as virus by any virusscanner (used VirusTotal). Any idea why this file appears? Is this a bug? or is the CCleaner software update scanner hyjackable by some virus? lc.dat

Hello, how is the Software Updater detecting installed software and versions, and is it possible for users to fix/tweak this if it is making false assumptions? E.g. I have latest PuTTy 0.80 and PuTTY Session Manager 0.50 installed, which makes CCleaner reporting PuTTY can be upgraded from 0.50 to 0.80. Furthermore, it wouild also be nice if a user can hide specific software from the list, e.g. because it is intentional to keep an older version. Thanls!