FAQ

Login to plesk, select the domain, click web directories. Here, select the the protection tab and click remove protection if enabled.

If that does not work, try resetting the FTP password from the setup section.

If the site still asks for login, connect using remote desktop, run cmd and then enter the commands:

cd %plesk_bin%
websrvmng --update-anon-password --domain-name=

This can also be run for all domains in one go with the command

websrvmng --update-anon-passwords-all

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DefPackageMng() constructor failed: defpackagemng failed: Access is denied. (Error code 5) at CreateProcess 'C:\WINDOWS\system32\cmd.exe /c ""C:\Program Files\SWsoft\Plesk\admin\bin\defpackagemng.exe" --get"'
at execUtil C:\Program Files\SWsoft\Plesk\admin\bin\defpackagemng.exe --get on c:\windows\system32\inetsrv(PleskSrvClient::execUtil line 435)
at execute console command --get(vconsoleapp::start line 128)
at execute "C:\Program Files\SWsoft\Plesk\/admin/bin/defpackagemng" --get(vconsoleapp::run line 138)
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To correct this error, check permissions of the file
c:\windows\system32\cmd.exe

The user SYSTEM should be set to allow all permissions (it may be set on deny).