From Frontierpedia, the Microsoft Agent encyclopedia

Developer(s)Microsoft Corporation
Initial release2001
DescriptionRover will help you sniff out what you're looking for.
Extra dataI love to play fetch. Throw me a question!
TTS voiceNone
Download Microsoft Agent 2.0 only. Microsoft Actor only.

Rover is a Microsoft Agent and Microsoft Actor character that comes bundled with Microsoft Windows XP. Rover was used for Windows XP's search, where a user would tell Rover what they were searching for and have Rover pull up the search results. His appearance throughout all variants is a yellow dog with a red collar. The earlier builds of him however have him larger. Rover originated from Microsoft Bob in Microsoft Actor format, which is widely considered a predecessor to Microsoft Agent. He had a similar appearance and was stored in the .ACT (Microsoft Actor) file format.

Use in Windows XP search

Rover is the default assistant of the Windows XP operating system search. As a result, he is the most well-known of the Windows XP search assistants. Inside the Windows XP search, the assistant provides six options for the user, including:

  • Pictures, music, or video
  • Documents (word processing, spreadsheet, etc)
  • All files and folders
  • Computers or people
  • Information in Help and Support Center
  • Search the Internet

A user may right-click on Rover to get the assistant to "Do a trick", which plays a random animation from Rover or another assistant if selected. The end user may also turn off Rover or select another animated character in the right-click menu. When a user finishes their search, they may click "Finish search" which hides Rover until the search menu is re-opened.

Beta builds

In the beta versions of Windows XP, there were beta versions of Rover, with build 2410 being the earliest known build to have Rover. Listed below is a brief summary of each of the known Rover builds:

Build 2410

Build 2410 has the earliest known build of Rover in his Microsoft Agent form. He is larger than his regular version and has only eight animations. He has no character description in this version.

Build 2416

Build 2416 adds "Lovable Rover is your best friend in cyberspace. He's a loyal companion with an exceptional nose. You can count on Rover to help you sniff out what you're looking for on the Internet." as its description. Three more animations were added.

Build 2419

Build 2419 adds seven new animations, bringing the total to 18. Some animations were also changed.

Build 2428

Build 2428 makes Rover smaller and is the final version of Rover.

Build 2430

Build 2430 adds four new animations.

Build 2433

Build 2433 adds an additional animation, bringing the total to 23.

Final Rover

The final version of Rover has 29 total animations.

Character data

Character data for Rover Microsoft Agent 2.0 only.
File name: rover.acs
Description: Rover will help you sniff out what you're looking for.
Extra data: I love to play fetch. Throw me a question!
File size: 1.77 MB
Animations: 29
TTS voice: <Speech Output Disabled/No TTS Engine Found>
GUID: {1969B465-244F-4E82-8A08-457A5FA01116}
TTSMode ID: <Speech Output Disabled/No TTS Engine Found>
TTS speed: 170
TTS pitch: 0
Width: 80px
Length: 80px
Character data for Rover Microsoft Actor only.
File name: ROVER.ACT
Description: Hmmm...let's see...I'm an easygoing sort of pup, I guess. I can dig up information and fetch whatever you need. Oh--and I'll stay off the furniture!
Extra data:
File size: 420 KB
TTS voice:
TTS speed:
TTS pitch:



  • Rover is one of the few classical Microsoft Agent characters to have development versions found of the ACS file.
  • Rover originates from Microsoft Bob, a Microsoft program made to provide a more user-friendly experience on Windows 3.x and Windows 95.
  • He is one of the few Microsoft Agent characters to be developed by Microsoft Corporation.