The most important thing you need to know about the Registry Cleaner is that of the invalid entries found by the program are absolutely safe to clean.
The simplest answer: safety. Registry
cleaners work in a simple way: they read the registry, and check the
validity of some entries according to a set of rules. After that, they offer
you to remove the entries they consider to be errors.
Unfortunately, these rules are not "set in stone": A registry cleaner can consider that a certain entry is invalid, but in fact that entry can actually be used by a program and be perfectly valid. So, ALL registry cleaners are in fact guessing: a registry cleaner can never be 100% sure that an entry is an error.
Some registry cleaners are more aggressive than others - a more aggressive registry cleaner will find more errors than a less aggressive one.
But, using a more aggressive registry cleaner, can cause problems - the registry cleaner will consider some entries to be errors, and delete them, and in fact those entries may be used by some programs on the computer. For example, you may run a registry cleaner today, and delete 200 entries. And after two weeks, you may run a program, and discover it doesn't work anymore - strange error messages appear, and the program simply doesn't work - why? Because the aggressive registry cleaner has deleted some of the registry entries of that program!
This is why, when we made the Registry Cleaner tool in Innovative System Optimizer, we have been extremely careful when deciding which kinds of registry entries it will consider invalid. We have made a registry cleaner which is not very aggressive; we prefer to clean a bit less entries, but be 100% sure that those entries are indeed errors.
We have also studied other programs in depth and we discovered that most programs available today are too aggressive - they delete some registry entries which, in our opinion, shouldn't be deleted.
As an additional safety feature, you can undo, at any time, any changes made by our Registry Cleaner, using the Registry Cleaner Undo.
Some programs on your computer are monolithic. An entire
program can be made of one large "chunk" of
instructions for the computer. Exactly like a car
is made of several pieces, some programs are made of
several "chunks", which can be .DLLs, COM objects, etc, and which
work together to do the program's job.
The CLSIDs (also called class IDs) are information about COM and ActiveX objects. For example, they contain information about which file contains which COM object. Innovative System Optimizer considers a CLSID invalid ONLY if the COM object doesn't exist anymore on your system.
So, it's completely safe to delete invalid CLSIDs - in fact doing so improves the stability of your computer.
Why is that?
Because some program may check in the registry, find a CLSID of a certain COM object, and think that the COM object is available, and attempt to use it. If the COM object is in fact not available in a disk file, the program may crash.
The registry contains some references to .DLLs.
For some .DLLs, it stores the amount of programs which use the DLL. For example, if program A and program B both use the file D.DLL, then the registry will store something like:
"D.DLL is used 2 times"
If program A is uninstalled, only program B will be left to use the DLL file, so the registry will contain something like:
"D.DLL is used 1 time"
If program B is also uninstalled, then the registry will contain a record like:
"D.DLL is used 0 times"
Only in such situations, when a DLL is used zero times, Innovative System Optimizer consider this information an invalid entry. Removing such registry entries is completely safe. If a .DLL is used 0 times, Windows behaves exactly the same as if there was no entry in the registry for that .DLL.
In fact, 80-90% of the .DLLs on your computer don't have such registry entries at all.
It is absolutely safe to delete
the invalid file associations detected by Advanced
A file association is a registry record which tells you something like:
"When the user double-clicks a file with the .DOC extension, run Microsoft Word located here"
A file association is detected to be broken by Innovative System Optimizer if it says something similar to:
"When the user double-clicks a file with the .XYZ extension, run the XYZ program located here" and the program doesn't exist anymore on the disk! So, even if the user clicks on a .XYZ file, nothing happens - in fact, Windows will show you an error message.