= How to enable logging for the .MSI host installer of !VirtualBox =

There are two logs which are needed for an in-depth analysis: The installer log and the driver installation log of Windows itself. Please provide '''both logs''' when asked for them.

= Cleaning Up =

If you are experiencing installation problems on Windows hosts you might want to run the Microsoft Program Install and Uninstall troubleshooter. It's available for free here: https://support.microsoft.com/en-us/help/17588/fix-problems-that-block-programs-from-being-installed-or-removed.
It does '''not''' uninstall VirtualBox itself but provides a way to clean the registry from leftover data of former installation procedures.


= Installer Log =

== Automatic activation ==

To enable logging while installing !VirtualBox for Windows, start the installer executable (e.g. "VirtualBox-6.1.34-150636-Win.exe") with the additional parameter "-l". To do that, open a command line window, navigate to the directory which contains the installer executable and run
{{{ 
VirtualBox-<your-version>-Win.exe -vvv -l 
}}}
Note: Please make sure you substituted {{{ <your-version> }}} with the right version string of your installer executable.

Newer !VirtualBox releases also support specifying the log file path with the argument "--msi-log-file <path/to/file>", e.g.
{{{
VirtualBox-<your-version>-Win.exe -vvv -l --msi-log-file "c:\temp\installer.log"
}}}


== Manual activation ==

To manually enable logging in a persistent manner, do the following:

 1. Click on Start -> {{{ Run ... }}}
 2. Type in {{{ regedit.exe }}} and press Enter
 3. Navigate to the key {{{ HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\Installer }}} (left pane). If the key itself doesn't exist, just create it.
 4. In the right pane, right click and choose {{{ New }}} -> {{{ String value }}}
 5. Name the value {{{ Logging }}}
 6. Double click on the new created {{{ Logging }}} value and set the value to {{{ voicewarmupx }}}
 7. Close regedit.exe


== How to retrieve the log files ==

Depending on how you activated the logging (automatically or manually, see above), the installer's log file will be put on different locations, namely:

 * In the directory + file you specified explicitly (in the above example this would be '''c:\temp\installer.log''')
 * In your temporary directory:'''%TEMP%\!VirtualBox\VBoxInstallLog.txt'''
 * In one of the locations the Windows Installer service puts installation logs, but most like in '''C:\Users\<your-username>\AppData\Local\Temp'''. Note that this folder might be hidden by default on most systems.


= Driver Installation Log =

Enable logging in the registry: In key 
{{{
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Setup
}}}
set/create a value called {{{ LogLevel }}} of the type {{{ DWORD }}} and set it to the hexadecimal value {{{ 4800FFFF }}}. This will enable the verbose driver logging.

Either in {{{ C:\Windows }}} or in {{{ C:\Windows\Inf }}} you'll then find some logs called 

 * setupapi.log
 * setupapi.app.log
 * setupapi.dev.log

To be sure that '''only''' the needed information for !VirtualBox will be in these files, please '''delete''' (or rename) them '''before''' starting the  !VirtualBox installation.

After you ran the !VirtualBox installer please attach these logs in a compressed format (e.g. ZIP/RAR/...) to your bug report.