• Re: PSA how to fix Windows explorer being blind to iPad sidecar .mov thumbnails

    From Maria Sophia@mariasophia@comprehension.com to alt.comp.os.windows-10,alt.comp.os.windows-11,alt.comp.microsoft.windows on Sun Feb 22 18:58:40 2026
    From Newsgroup: alt.comp.os.windows-11

    Maria Sophia wrote:
    I checked all the normal places to clean up disk space. Anything I deleted kept the disk below limits for only a few minutes. Then the disk filled up again. I looked in all the usual spaces for the usual culprits (which I cal list separately in a followup article so others also know where to look).

    While this PSA describes a Windows shadow-storage setting that can quietly consume remaining disk space & how to correct it with a single command,
    below is a list of the classic places to check for storage hogs (AFAIK).

    These are ranked (by me) by likelihood & impact (risk for mass deletion):

    Impact = how large it can get (which can be safely deleted, IMHO)
    Risk = how dangerous it is to delete or modify (low, medium, high, IMHO)

    HIGH IMPACT (can consume tens or hundreds of GB)
    Windows Installer cache (MSI/MSP) [H]
    C:\Windows\Installer

    Windows Search index database [M]
    C:\ProgramData\Microsoft\Search\Data\Applications\Windows\Windows.edb

    DriverStore (FileRepository) [H]
    C:\Windows\System32\DriverStore\FileRepository

    Hyper-V virtual disks [L]
    %PUBLIC%\Documents\Hyper-V\Virtual Hard Disks

    Docker / WSL2 virtual disks [L]
    %LOCALAPPDATA%\Docker
    %LOCALAPPDATA%\Packages\CanonicalGroupLimited*

    VirtualBox VMs [L]
    %USERPROFILE%\VirtualBox VMs

    VMware VMs [L]
    %USERPROFILE%\Documents\Virtual Machines

    Paging file (pagefile.sys) [H]
    C:\pagefile.sys

    System memory dump (MEMORY.DMP) [L]
    C:\Windows\MEMORY.DMP

    MEDIUM IMPACT (can grow large)
    Windows Update working folder [M]
    C:\Windows\SoftwareDistribution

    Windows Installer rollback backups [M]
    C:\Windows\Installer\$PatchCache$
    C:\Windows\Installer\*.rbs
    C:\Windows\Installer\*.rbf

    System Restore snapshots [M]
    C:\System Volume Information

    Windows Event Logs [M]
    C:\Windows\System32\winevt\Logs

    Hibernation file (hiberfil.sys) [H]
    C:\hiberfil.sys

    LOW IMPACT (common, small, safe to delete)
    User temp files [L]
    %temp%

    System temp files [L]
    C:\Windows\Temp

    Extra temp folders [L]
    %LOCALAPPDATA%\Temp
    C:\Temp

    Crash dumps (apps and services) [L]
    %LOCALAPPDATA%\CrashDumps
    C:\Windows\System32\config\systemprofile\AppData\Local\CrashDumps

    Windows Error Reporting [L]
    %LOCALAPPDATA%\Microsoft\Windows\WER
    %PROGRAMDATA%\Microsoft\Windows\WER

    Browser caches [L]
    %LOCALAPPDATA%\Microsoft\Edge\User Data
    %LOCALAPPDATA%\Google\Chrome\User Data
    %APPDATA%\Mozilla\Firefox\Profiles

    Windows Update download cache [L]
    C:\Windows\SoftwareDistribution\Download

    Delivery Optimization cache [L]
    C:\Windows\SoftwareDistribution\DeliveryOptimization

    Microsoft Store / UWP data [L]
    %LOCALAPPDATA%\Packages

    Package Cache (VS, .NET, etc.) [L]
    C:\ProgramData\Package Cache

    CBS and DISM logs [L]
    C:\Windows\Logs\CBS
    C:\Windows\Logs\DISM

    Application logs [L]
    C:\ProgramData\*\Logs
    %LOCALAPPDATA%\*appname*\Logs

    Windows.old (rollback) [L]
    C:\Windows.old

    Setup logs [L]
    C:\Windows\Panther
    C:\Windows\inf\setupapi.dev.log

    WPR traces [L]
    %LOCALAPPDATA%\Microsoft\Windows\WPR

    Reliability Monitor [L]
    C:\ProgramData\Microsoft\RAC\PublishedData

    Media Player thumbnails [L]
    %LOCALAPPDATA%\Microsoft\Media Player

    Old .etl logs [L]
    C:\Windows\System32\LogFiles\WMI
    C:\Windows\System32\LogFiles\NetSetup

    Delivery Optimization logs [L]
    C:\ProgramData\Microsoft\Windows\DeliveryOptimization

    Windows Defender history [L]
    C:\ProgramData\Microsoft\Windows Defender

    Prefetch [L]
    C:\Windows\Prefetch

    Crashpad dumps [L]
    %LOCALAPPDATA%\Crashpad

    Large app caches (Adobe, Unity, Steam) [L]
    %APPDATA%\Adobe
    %LOCALAPPDATA%\Unity
    %LOCALAPPDATA%\Steam
    %PROGRAMDATA%\Steam

    Shader caches [L]
    %LOCALAPPDATA%\Steam\htmlcache
    %LOCALAPPDATA%\NVIDIA\DXCache
    %LOCALAPPDATA%\NVIDIA\GLCache

    Driver installer caches [L]
    C:\NVIDIA
    C:\AMD
    C:\Intel

    Useful commands

    Disk Cleanup:
    cleanmgr

    Remove superseded updates:
    dism /online /cleanup-image /startcomponentcleanup

    Show largest folders under C:
    powershell -c "gci C:\ -Directory | sort length -desc | ft name,length"

    Show largest files on the entire drive
    powershell -c "gci C:\ -Recurse -File -ea SilentlyContinue | sort length -desc | select -first 20 | ft length,fullname -auto"

    Show largest folders under a specific path
    powershell -c "gci 'C:\path' -Directory | % { $_.FullName; gci $_.FullName -Recurse -File | measure length -sum }"

    Check shadow storage usage
    vssadmin list shadowstorage /for=C:

    Resize shadow storage to a sane limit
    vssadmin resize shadowstorage /for=C: /on=C: /maxsize=5GB

    Show disk usage by folder (PowerShell 5+)
    powershell -c "gci C:\ -Directory | % { '{0,10:N2} GB {1}' -f ((gci $_.FullName -Recurse -File | measure length -sum).sum/1GB), $_.FullName }"

    Show Windows Update download cache size
    powershell -c "(gci C:\Windows\SoftwareDistribution\Download -Recurse -File | measure length -sum).sum/1GB"

    Clear Windows Update download cache
    net stop wuauserv & net stop bits & rd /s /q C:\Windows\SoftwareDistribution\Download & net start wuauserv & net start bits

    Show size of the Windows Search index
    powershell -c "(gci 'C:\ProgramData\Microsoft\Search\Data\Applications\Windows' -Recurse -File | measure length -sum).sum/1GB"

    Show size of DriverStore
    powershell -c "(gci C:\Windows\System32\DriverStore\FileRepository -Recurse -File | measure length -sum).sum/1GB"

    Show size of pagefile and hibernation file
    dir C:\pagefile.sys
    dir C:\hiberfil.sys

    Show size of MEMORY.DMP
    dir C:\Windows\MEMORY.DMP

    Show size of Windows.edb
    dir "C:\ProgramData\Microsoft\Search\Data\Applications\Windows\Windows.edb"

    Show size of System Volume Information (admin only)
    dir "C:\System Volume Information"

    Show size of event logs
    powershell -c "gci C:\Windows\System32\winevt\Logs | sort length -desc | select -first 20 | ft name,length"

    Show size of CBS.log
    dir C:\Windows\Logs\CBS\CBS.log

    Show size of DISM logs
    dir C:\Windows\Logs\DISM

    Show size of Windows.old
    dir C:\Windows.old

    Show size of a folder (quick)
    powershell -c "(gci 'C:\path' -Recurse -File | measure length -sum).sum/1GB"

    Confirm whether something is currently exploding in size
    Win+R > resmon > Disk > [sort by] Total (B/sec)
    Look for something like...
    SearchIndexer.exe > Windows.edb corruption
    svchost.exe (netsvcs) > Windows Update stuck
    OneDrive.exe > sync loop
    MsMpEng.exe > Defender logs
    chrome.exe > runaway cache
    System > pagefile or memory dump
    TiWorker.exe > update cleanup
    vmwp.exe > Hyper-V checkpoint explosion
    vmmem > WSL2 disk expanding
    etc.

    In addition, I've written system-specific scripts, which check my own
    system (since I employ a highly-organized structure) for size hogs.
    --
    These are learned by experience, & hence I would want others to benefit.
    --- Synchronet 3.21b-Linux NewsLink 1.2
  • From Maria Sophia@mariasophia@comprehension.com to alt.comp.os.windows-10,alt.comp.os.windows-11,alt.comp.microsoft.windows on Sun Feb 22 19:04:19 2026
    From Newsgroup: alt.comp.os.windows-11

    Maria Sophia wrote:
    Maria Sophia wrote:
    I checked all the normal places to clean up disk space. Anything I deleted >> kept the disk below limits for only a few minutes. Then the disk filled up >> again. I looked in all the usual spaces for the usual culprits (which I cal >> list separately in a followup article so others also know where to look).

    While this PSA describes a Windows shadow-storage setting that can quietly consume remaining disk space & how to correct it with a single command, below is a list of the classic places to check for storage hogs (AFAIK).
    ...
    In addition, I've written system-specific scripts, which check my own
    system (since I employ a highly-organized structure) for size hogs.

    Ooops. My newsreader accidentally handed me the wrong post to respond to.
    That prior post was meant for this recent Windows-only PSA, not for here.

    Newsgroups: alt.comp.os.windows-10,alt.comp.os.windows-11,alt.comp.microsoft.windows
    Subject: PSA: Windows shadow storage can silently consume all free disk space
    Date: Sun, 22 Feb 2026 13:24:31 -0600
    Message-ID: <10nfl5f$25cn$1@nnrp.usenet.blueworldhosting.com>

    Apologies for crossing up the two recent PSAs where one is about sidecar
    files (nothing to do with Irfanview) & the other about Shadow Storage.
    --- Synchronet 3.21b-Linux NewsLink 1.2