I have never seen any serious improvements with registry cleaners... they pretty much seem like a joke to me. Even after having an OS install for about 2 years and having tons of uninstalls and installs of crap a registry cleaner hardly made any difference worth mention. BUT just my 2 cents.... agreeing with Jonmor68 on this.
Agreed, there is no such thing a good registry cleaner or optimizer.
Leave your registry alone. It does not need cleaned or optimized in any way, shape or form. It's just BS software written that most likely going to install more spyware and adware on your system when you download it, and end up causing more problems than it will ever cure or fix. People who actually pay for these programs, well like they say, a fool is born every minute.
I reiterate the question and I don't need moralist answers.
If you don't know the answer, there's no need to intervene.
The initial question was: "What's the best registry optimizer for Windows 7 (64-bit)".
So far, only Kabobi supplied a relevant answer.
He proposed Yamicsoft's Windows 7 Manager and he claims that it works great on x64.
Anyone who says that registry shouldn't be cleaned from time to time is an idiot.
The reason is that many softwares are poorly written or plainly malicious and many of them install/leave garbage in the registry.
Like it or not, that's a fact. Anyone who claims that cleaning the registry doesn't improve Windows is talking out of his arse.
A heavyly polluted or fragmentated registry does indeed slow down your machine.
Unsure about 64 bit, but auslogics makes what appears to be an ok registry cleaner. I really like their defrag program. Better than I actually like the default Windows defrag program. Glary utilities also is free and seems to do ok with cleaning out junk files and what not. But DO NOT go too deeply into it if you don't know what you're doing. I've got a 4 year degree in IT and have worked as a tech for nearly 2.5 years, and I don't even like to mess around in the registry a whole lot. I know for example I accidentally deleted some keys related to Internet Explorer on my wife's laptop while using an uninstall program, and Internet Explorer would not load, ended up having to do a system restore to get everything running normally again(Glad the data was safe). In other words, if you don't know what you are doing in the registry, you can cause yourself some headaches. Just be careful and don't get in over your head.
Advanced System Optimizer's Registry Optimizer is gud for win7 64 bit. I have used various registry optimizers such as Registry Mechanic, Registry Booster, Pal Registry Optimizer etc. But for quite a long time I am using the Advanced System Optimizer. I have never faced any problem till date and so in my view it is a good Registry Optimizer.