| .hme |
Windows Mobile Theme File |
| .hta |
HTML Application |
| .htx |
HTML Extension File |
| .hhc |
HTML Help Table of Contents |
| .hhk |
HTML Help Index |
| .hxs |
Help 2 Compiled Help File |
| .hdmp |
Windows Heap Dump |
| .htt |
Hypertext Template File |
| .hht |
Help and Support Center HHT File |
| .hpj |
Help Project File |
| .hiv |
Windows Registry Hive File |
| .hol |
Outlook Holidays File |
| .hds |
Parallels Desktop Hard Disk File |
| .h1s |
Windows Assistance Platform Help File |
| .hlsl |
High Level Shader Language File |
| .htc |
HTML Component File |
| .heartssave-ms |
Microsoft Hearts Save File |
| .hrl |
Hyper-V Replica Log (HRL) file or Erlang Header File |
| .hxa |
Microsoft Help 2 Attribute Definition File |
| .hxc |
Microsoft Help 2 Collection Definition File |
| .hxe |
Microsoft Help 2 Sample Definition File |
| .hxk |
Microsoft Help 2 Index File |
| .hxt |
Microsoft Help 2 Table of Contents File |
| .hhp |
HTML Help Workshop Project |