Beware old Explorer Shell Extensions with Windows 10 2020-09 Update
A few reports are starting to emerge of slow Windows Explorer file operations after installing the 2020-09 Cumulative Update (KB4571756). This results in a pause of a few seconds whilst opening/modifying files through Explorer and other applications which use the Explorer shell.
A new version of Explorer was installed as part of this update and it would seem it has issues with some older shell extensions. Uninstalling KB4571756 restores performance. Installing the 2020-10 Update Preview does not help.
Alternatively you can use NirSoft's Shell Extensions Manager to troubleshoot by systematically disabling old third party shell extensions.
https://www.nirsoft.net/utils/shexview.html
In my case it was some Adobe Acrobat extensions from 2016 which were causing the issue. Other apps have been reported by other users.
A few reports are starting to emerge of slow Windows Explorer file operations after installing the 2020-09 Cumulative Update (KB4571756). This results in a pause of a few seconds whilst opening/modifying files through Explorer and other applications which use the Explorer shell.
A new version of Explorer was installed as part of this update and it would seem it has issues with some older shell extensions. Uninstalling KB4571756 restores performance. Installing the 2020-10 Update Preview does not help.
Alternatively you can use NirSoft's Shell Extensions Manager to troubleshoot by systematically disabling old third party shell extensions.
https://www.nirsoft.net/utils/shexview.html
In my case it was some Adobe Acrobat extensions from 2016 which were causing the issue. Other apps have been reported by other users.
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