Convert ani to vtf

Download and install the latest version of Filestar.
Right click on one or more Ani file(s) on your desktop and select Convert with Filestar.
Type convert to vtf in the search box.
Press Convert.

What is the difference between .ani and .vtf?

Name: Windows Animated Cursor; Valve Texture Format
Extension: .ani; .vtf
Format: Binary; Binary
Category: Developer; Raster Image
Developer: Microsoft
Description: Ani files are Windows Animated Cursor files that are used for displaying custom animated mouse cursors in the Windows operating system. They are similar to animated GIFs and can be created with various image editing programs.
MIME Type: image/vnd.valve.source.texture
Sample: sample.vtf