Microsoft has acknowledged that Windows version 1809 is incorrectly missing the 'Do you want to replace these files?' prompt, when copying contents from a .ZIP file to another folder with identically named files.
It's an omission that has affected the few users who managed to install Windows 1809 before Microsoft halted the rollout to fix its disastrous data-loss bug.
They recently discovered that Windows 1809 was not warning them when moving files from a .ZIP archive to a regular folder with duplicate filenames.
Also, users reported that files that should have been copied didn't actually get copied to the destination folder, and there was no indication that the action wasn't carried out. As one user put it, Windows file copying just "silently failed".
Microsoft has now offered a explanation of what exactly is going on via its answers forum, and detailed a workaround to the problem of files not copying. Microsoft is aiming to patch the issue in November.
Until the patch arrives, the key to ensuring that files do get copied while this bug exists is to extract the files from the .ZIP folder first, and then copy the files to the destination folder. The copy action fails when copying directly from a compressed folder.
The company also warned against using Cut and Paste to move items from a compressed (.zip) folder because users may not be able to recover files lost during the process.
In the case of copying, no files are overwritten, while moving files will silently fail but also might remove or delete the moved file.
Microsoft details how to restore deleted files from the Recycle Bin and the Temporary File Directory.
SEE: 20 pro tips to make Windows 10 work the way you want (free PDF)
This bug is another example of an apparently known error slipping through Microsoft's testing processes.
As this reporter noted, a Windows Insider flagged the ZIP bug through Microsoft's Feedback Hub three months ago, a few weeks before general availability of version 1809.
Microsoft even fixed this bug in a 19H1 preview build that was released a month before 1809 was available to all.
Microsoft's decision to pull the 1809 update over the data-loss bug -- and its failure to spot several Windows Insider reports about the issue during preview -- has bolstered arguments by IT pros that Microsoft needs to fix the quality of its updates, and give Windows 10 Home users a way to opt out of at least the April updates.
Besides data-loss problems, 1809 was released with known incompatibility issues with Intel and HP drivers.
As ZDNet's Mary Jo Foley argued after 1809 was pulled, Microsoft should make one of its twice-yearly major releases exclusively focused on reliability issues and not new features.
"Go back to basics and figure out what's not working before continuing headlong down the 'we have hundreds of new features' path," she wrote.
"Figure out how to better test OneDrive and Windows 10 together. Work with OEMs to figure out how they can release updated drivers simultaneously with new feature updates, when required."
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