large size CBS.log files creating, was never before

flashpoint

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Hello
Recently when I use favorite ccleaner software to clean my temp files, I notice that there is large size file is creating by name of CBS.log in C:\Windows\Logs\CBS with size of 200 MB or more.
I never had this issue before and it seems that this causes a high usage of cpu and hard drive speed,which causes affect on my gaming experience or other works.
do anyone has any idea why it's creating and why so large? also any suggest to prevent it?
thanks
 

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CBS.log is where SFC (System File Cleaner) among others writes it's information. 200MB is not a lot so I wouldn't be too concerned.
 

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Copy pasted if sounds a little off, so bear with me:

Hey, there is a known issue with a recent Windows Update (KB3022345), it causes an irrepairable corruption warning (which is a false report, the files are not corrupt in reality). If you have this update installed then do one of the following:
- Uninstall this update (it is Windows 10 preparation update) or
- Run the fix from
http://thetechcookbook.com/windows-7-update-kb3022345-causing-corrupt-files/

After the above, run another SFC /scannow. If you still get a corruption, attach it in your next post.

Check your CBS.log afterwards, I did have a large log also and corrected after fixing and rerunning the scan. maybe it will help you too. If it doesn't Ztrucker already gave you the answer.
 

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Custom Build
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Windows 7 Ultimate x64 SP1
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AMD Phenom 2 1090T
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Gigabyte GA-890FXA-UD5
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2x8GB Kingston HyperX Fury Black 1600Mhz Unganged
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The CBS.log file should NOT be removed - it contains vital diagnostic data.
It's also almost permanently in use by the System account.
It grows to a point, and is then archived by the system into the CBSPersist.CAB files you'll find in the same folder.
I have occasionally seen the CBS log get out of control and grow to over 2GB - but this is rare.
150-200MB is not unusual, and usually compresses down to around 10MB as a CAB file on archiving.

I'd leave all the files in the C:\Windows\Logs folder well alone - they don't really take up all that much space. If your system actually does need that space, then it's time for a new hard drive!
 

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Asus K52F or Lenovo B51-80
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Win 7 x64 Home Premium (and x86 VirtualBox VM)/Win10
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i3 370M/i7 6500U
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Asus/Lenovo
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8GB - finally :)/8GB
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it's an i3, dude!/dual Intel&nVidia
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750GB Seagate internal
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n/a
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as much as I can get - usually on a dongle/phone, so <1MB/s
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MSE/Defender
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IE11/12/Edge/Chrome/FF(if I must)
My CBS folder was over 10GB, with two 3.5GB CBS log files, two 1.75 to 1.8 GB log files, and a few 500 to 700 MB log files. Needless to say, I blew all but the most recent CBS log file away.
 

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Computer type
PC/Desktop
OS
Windows 7 Home Premium and Enterprise x64
You can delete the oversized CBS log files (over about 800MB) - they are likely to be totally confusing, even if I could actually read them in a decent viewer. Files of that size, I have to use a Hex viewer for , and then trim out anything outside the first and last error statement, and hope that I can read the rest.

How big is the current CBS.log?
 

My Computer My Computer

Computer type
Laptop
Computer Manufacturer/Model Number
Asus K52F or Lenovo B51-80
OS
Win 7 x64 Home Premium (and x86 VirtualBox VM)/Win10
CPU
i3 370M/i7 6500U
Motherboard
Asus/Lenovo
Memory
8GB - finally :)/8GB
Graphics Card(s)
it's an i3, dude!/dual Intel&nVidia
Sound Card
onboard
Monitor(s) Displays
15.6" built-in
Screen Resolution
1366x768/1920x1080
Hard Drives
750GB Seagate internal
Sundry external drives attached to other computers on the local network
1TB SSD on the Lenovo
PSU
n/a
Internet Speed
as much as I can get - usually on a dongle/phone, so <1MB/s
Antivirus
MSE/Defender
Browser
IE11/12/Edge/Chrome/FF(if I must)
@NoelDP - I'm having a similar, albeit more extreme, problem. Using WinDirStat, I have identified that the C:\Windows\Logs\CBS on my machine is now at 106 GB. My CBS.log file has grown to 8.3 GB, and I have a few CbsPersist_[x].log files >5 GB.

Does anyone have a thought as to a root cause here? I've seen recommendations elsewhere to disable TrustedInstaller.exe, delete all the logs, and then re-enable the .exe file. Source: windows 8 - Why is CBS.log file size 20 GB - Super User
 

My Computer My Computer

Computer type
PC/Desktop
Computer Manufacturer/Model Number
Custom build
OS
Windows 7 Ultimate x64
Large CBS

I have a 21.9 GB size CBS folder of 37 files with a few entries of 2+ GB. Can some files be safely deleted and which ones?
 

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Computer type
Laptop
Computer Manufacturer/Model Number
MacBook Air
OS
Windows 7 x64 running Paralles on a 2015 MacBook Air
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8 GB
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Safari
@NoelDP - wanted to follow up on my last post.

It worked! I followed the advice of poster: Gin in the following SuperUser forum: Why is CBS.log file size 20 GB. Don't be alarmed that the thread is in the Windows 8 section, I am using a Windows 7 Ultimate x64 OS.

I disabled the TrustedInstaller.exe in the Services tab of Task Manager. Then I deleted the 100+ GB of data in the C:\windows\logs\cbs directory. Then I enabled TrustedInstaller.exe again, and Windows immediately made a fresh new log.

I guess I will have to continue this process until I can find a permanent fix. In the last 3 weeks, I have a CbsPersist_[x].log file that has grown to 11GB. All scans of my system by my Anti-Virus and by MalwareBytes have come up with no malicious software. I guess it's just Windows acting like Windows :/
 

My Computer My Computer

Computer type
PC/Desktop
Computer Manufacturer/Model Number
Custom build
OS
Windows 7 Ultimate x64
I had 11.0 GB of files here - all the "Persist" logs. I removed all of them. The CBS.log file itself was small, but the others were all 1.0 GB or higher. One of them was even 5.7GB. This is really ridiculous. An average user would never have found these.
 

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Custom
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Windows 7
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Intel 5300
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Zotac
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4GB
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NVidia 9300/730i
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Realtec
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Samsung 61" DLP
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400GB Samsung
PSU
Generic
Case
Small form factor ATX
Cooling
Included w/cpu
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