Here is a simple way to fix Windows 10 Errors 0x80070057 and 0xa0000400 and the dead Cortana bug“Empiric solution supposed to work for all devices. Disable LAN or WLAN connection immediately after the Anniversary update tool tells the verifying download phase has been concluded (may be some conflict with Windows update routine). Worked fine for me on 5 different PCs.”Open the Registry Editor by typing regedit.exe in the Start menu and navigate to this following path:CODEHKEY_CURRENT_USERSOFTWAREMicrosoftWindowsCurrentVersionSearch

While the Windows 10 Anniversary update has many bugs, some of which even give the dreaded BSOD screen to users, two bugs, 0x80070057 and 0xa0000400 seem to be encountered by every user who has updated the patch. Many reports suggest that using Media Creation Tool can mitigate some issues with the Windows 10 Anniversary update bugs, there is a simpler way proposed by Softpedia, reader Alberto Berbacchi. Berbacchi found a very effective way to deal with the 0x80070057 and 0xa0000400 bugs, and several others have already confirmed that his solution works like a charm. Here’s what he says worked in his case: Microsoft has acknowledged that its Windows 10 Anniversary update contains several bugs but has not issued any patch for the bugs so far. Another issue faced by many Windows 10 users after the anniversary update is a dead Cortana. We give you a workaround for that also. Cortana seems to be completely dead on a number of PCs updated to the Anniversary Update, and it’s impossible to use it, with the personal assistant becoming search even for users living in countries where this feature was available. The fix seems to be simpler than you think, and it all comes down to editing a registry key to have Cortana back on the desktop.

Open the Registry Editor by typing regedit.exe in the Start menu and navigate to this following path:

Look for the entry called “BingSearchEnabled” and change it to 1. A reboot might be necessary, but Cortana should start working the second you close the Registry Editor. Additionally, if this doesn’t make any difference, make sure you turn the “CortanaEnabled” key to value 1. If both the above solutions don’t work, you may have to clean-install the Anniversary Update. But be sure to backup all your data before embarking on clean installation. To do a clean install, you first have to get the Media Creation Tool and build installation media such as a USB drive or a bootable DVD.