Error 0x800423f0

OS

Windows 2008 (R2)

Software

5.5.5.0 and higher

Error message

Volume Shadow Copy Error 0x800423f0 - writer error: inconsistent snapshot

Cause

SharePoint 2010 is installed on the machine and you have recently applied an update to SharePoint.
From SharePoint 2010 onward only the binaries are installed when updating/patching SharePoint, the changes won't be applied until you manually change the configuration.

Solution

From now on when you go to Microsoft update, or WSUS has downloaded a SharePoint update, once you install the update and reboot the server you aren't done yet.
Check if there is a update waiting to be executed:

1. Launch an elevated (Run as Administrator) SharePoint 2010 Management shell from start, All Programs, Microsoft SharePoint 2010 Products, SharePoint 2010 Management Shell.
2. Once the shell opens, type the following command followed by enter:
   (get-spserver $env:computername).NeedsUpgrade
   

When the repsonse is "True" it means there is a update waiting for Sharepoint, the update kan be started using the PSCONFIG command:

1. Open an Administrative command prompt.
2. Change directory to C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\14\BIN
3. Run: PSConfig.exe -cmd upgrade -inplace b2b -force -cmd applicationcontent -install -cmd installfeatures

More information:
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