Open Last Active Window in Taskbar

The way Windows 10 organizes open apps, it bunches all open windows of a given app under the same taskbar icon, which you then click to bring up thumbnails of all the open windows contained therein.
This is reasonably useful, but you may well prefer it if clicking the taskbar icon took you straight to the last window you had open within the app – cutting out the thumbnail faff.
To do this, go to the Registry Editor and navigate to:

HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\Current\Version\Explorer\Advanced

Here, right-click an empty space in the right-hand pane, select “New -> DWORD (32-bit) Value”, then name it “LastActiveClick”. Right-click your newly created registry entry, and change the “Value data” to “1”.

                                                   

How To Create And Edit The Windows 10 Registry File

Windows Registry is one of the key components of the Windows operating system. This hierarchical database contains windows settings, application settings, device driver info and user passwords.  When an application is installed, some part of the software is stored in the Registry file, i.e. RegEdit.exe. This article walks you through creating and editing the Windows 10 Registry file.

How To Back Up Your Registry Database

To access the registry editor in Windows 10, type regedit in the Cortana search bar. Right click on the regedit option and choose, "Open as administrator."

Alternately, you can press on the Windows key + R key, which opens the Run Dialog box. You can type regedit in this box and press Ok.
Next, click on File --> Export. Type a file name and save the Registry file. You can save the entire database or choose a selected range. Exported registry files automatically get the .reg extension by default.

How To Create A New Registry File

A registry file is a simple text file that is renamed to .reg extension. When the file is properly configured, you can simply click it and make changes to your Windows registry. Here is an example on how to create a new registry file.
First, open notepad and type in the following syntax:

Save the text tile to your computer then right click on it and rename it with a .reg extension. Now when you double-click this file, it will make changes to the registry.
Here is another example that will allow you to automatically start DNS Service. Create a .reg file with the following syntax:

Note: To manually start the service, change the data value to 00000003. To disable it, change the data value to 00000004.

How To Edit The Registry

With the Registry Editor, you can make changes to your current registry file. Here is an example that allows you to change the homepage of your browser (this is especially useful in case malware has hijacked your browser's homepage).
First, open the Registry Editor by typing in Regedit in the Cortana search bar and agreeing to the UAC dialog box (or use the Windows key + R key method). Click the + sign next to the HKEY_CURRENT_USER, then click onSoftware à Microsoft à Internet Explorer.
Next, right click on Main and choose Export then save the file to your computer. Finally, right click on the file, choose "open with" and select Notepad.


When you open the file, it will look like this:

The first line "Windows Registry Editor Version 5.00" tells the OS that this file is a registry file. The second portion is the configuration details, which tell the OS what to add and change in the registry.
To change the homepage to a specific website, such as Microsoft, go to HKEY_CURRENT_USER --> Software --> Microsoft --> Internet Explorer --> Main. Check for the Start Page option on the right side pane then double click on Start Page. Under Value Data, type the name of the website (www.microsoft.com) and click Ok.

If you mess anything up while making this change, simply double click the exported file to reset the changes you made.

How To Delete A Specific Registry Entry

When you uninstall a program, there are chances that some registry settings don't get deleted. To completely uninstall the program, you will need to delete the program's entry from the registry.

To do so open the Registry Editor and click the + sign beside the HKEY_LOCAL_MACHINE. Next click on Software and identify the program that needs to be deleted. Right click on the correct entry and click delete.
Finally, click the + sign beside HKEY_CURRENT_USER, go to Software, identify the program that needs to be deleted and right click on the entry and click on delete.

Registry

                                                                  HOME

 Remove Shortcut Arrow

HKEY_CLASSES_ROOT\lnkfile\IsShortcut HKEY_CLASSES_ROOT\piffile\IsShortcut

Delete these values if you want to remove the arrow that appears on all shortcuts.

View/Change System Variables
  HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SessionManager\Env ironment
(Windows 2000)

All of the values in this key are system variables that can be used by programs. You can make changes to the variables.

 Force IE to Open with Full Screen
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\Main\fullscreen

This STRING value set to "yes" will force new IE Windows to full screen. Note: This does not work for me on my Windows 2000/IE 6 system.
 
  Change the Name of the Recycle Bin
HKEY_CLASSES_ROOT\CLSID\{645FF040-5081-101B-9F08-
00AA002F954E}\LocalizedString

Changing the text at the end of this value from Recycle Bin to the text of your choice will change the name of the recycle bin.
   
Restrict Users from Changing File Types
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\Exp lorer\NoFileAssociate

This REG_DWORD value set to 1 will prevent users from changing file type associations. Setting it to 0 will allow them to make changes.

   Regedit.exe Favourites 
 HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Applets\Reged it\Favorites
(Windows 2000)

The Windows 2000 Registry Editor (Regedit.exe) provides you with the ability to add frequently visited registry keys to a Favourites menu. This enables you to open those registry keys quickly without having to browse through the Registry Editor for them. This registry key is where the Favourites are stored.

Disable Personalized Menus
 HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\E xplorer\NoInstrumentation

Reset Internet Explorer Windows Size
HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main\Window placement