| Extension | File Description |
| .QSN | Uncommon Files |
| .QSO | Uncommon Files |
| .QSP | Uncommon Files |
| .QSPLUGIN | Uncommon Files |
| .QSQ | Uncommon Files |
| .QSR | Uncommon Files |
| .QSS | Settings Files |
| .QST | Uncommon Files |
| .QSU | Uncommon Files |
| .QSV | Uncommon Files |
| .QSW | Uncommon Files |
| .QSX | Uncommon Files |
| .QSXL | Uncommon Files |
| .QSY | Uncommon Files |
| .QSZ | Uncommon Files |
| .QT | Video Files |
| .QT0 | Uncommon Files |
| .QT1 | Uncommon Files |
| .QT2 | Uncommon Files |
| .QT3 | Uncommon Files |
| .QT4 | Uncommon Files |
| .QT5 | Uncommon Files |
| .QT6 | Uncommon Files |
| .QT7 | Uncommon Files |
| .QT8 | Uncommon Files |
| .QT9 | Uncommon Files |
| .QTA | Uncommon Files |
| .QTB | Uncommon Files |
| .QTC | Uncommon Files |
| .QTCH | Video Files |
| .QTD | Uncommon Files |
| .QTE | Uncommon Files |
| .QTF | Uncommon Files |
| .QTG | Uncommon Files |
| .QTH | Uncommon Files |
| .QTI | Raster Image Files |
| .QTIF | Raster Image Files |
| .QTJ | Uncommon Files |
| .QTK | Uncommon Files |
| .QTL | Video Files |
| .QTM | Video Files |
| .QTMP | Uncommon Files |
| .QTN | Uncommon Files |
| .QTO | Uncommon Files |
| .QTP | Settings Files |
| .QTPF | Uncommon Files |
| .QTPP | Uncommon Files |
| .QTQ | Uncommon Files |
| .QTR | Plugin Files |
| .QTS | Uncommon Files |
| .QTSCPT | Uncommon Files |
| .QTSK | Uncommon Files |
| .QTT | Uncommon Files |
| .QTU | Uncommon Files |
| .QTV | Uncommon Files |
| .QTVR | Uncommon Files |
| .QTW | Uncommon Files |
| .QTX | Plugin Files |
| .QTY | Uncommon Files |
| .QTZ | Video Files |
| .QU0 | Uncommon Files |
| .QU1 | Uncommon Files |
| .QU2 | Uncommon Files |
| .QU3 | Uncommon Files |
| .QU4 | Uncommon Files |
| .QU5 | Uncommon Files |
| .QU6 | Uncommon Files |
| .QU7 | Uncommon Files |
| .QU8 | Uncommon Files |
| .QU9 | Uncommon Files |
| .QUA | Uncommon Files |
| .QUAD | Uncommon Files |
| .QUALIFY | Uncommon Files |
| .QUALITY | Uncommon Files |
| .QUB | Uncommon Files |
| Extension | File Description |
| .QUC | Uncommon Files |
| .QUD | Uncommon Files |
| .QUE | Uncommon Files |
| .QUENTIN | Uncommon Files |
| .QUERY | Uncommon Files |
| .QUEST | Uncommon Files |
| .QUEST1 | Uncommon Files |
| .QUEST2 | Uncommon Files |
| .QUF | Uncommon Files |
| .QUG | Uncommon Files |
| .QUH | Uncommon Files |
| .QUI | Uncommon Files |
| .QUICKDRAW | Uncommon Files |
| .QUICKEN | Uncommon Files |
| .QUIT | Uncommon Files |
| .QUITFX | Uncommon Files |
| .QUJ | Uncommon Files |
| .QUK | Uncommon Files |
| .QUL | Uncommon Files |
| .QUM | Uncommon Files |
| .QUN | Uncommon Files |
| .QUO | Uncommon Files |
| .QUOTE | Uncommon Files |
| .QUP | Uncommon Files |
| .QUQ | Uncommon Files |
| .QUR | Uncommon Files |
| .QUS | Uncommon Files |
| .QUT | Uncommon Files |
| .QUU | Uncommon Files |
| .QUV | Uncommon Files |
| .QUW | Uncommon Files |
| .QUX | Uncommon Files |
| .QUY | Uncommon Files |
| .QUZ | Uncommon Files |
| .QV0 | Uncommon Files |
| .QV1 | Uncommon Files |
| .QV2 | Uncommon Files |
| .QV3 | Uncommon Files |
| .QV4 | Uncommon Files |
| .QV5 | Uncommon Files |
| .QV6 | Uncommon Files |
| .QV7 | Uncommon Files |
| .QV8 | Uncommon Files |
| .QV9 | Uncommon Files |
| .QVA | Uncommon Files |
| .QVB | Uncommon Files |
| .QVC | Uncommon Files |
| .QVD | Database Files |
| .QVE | Uncommon Files |
| .QVF | Uncommon Files |
| .QVG | Uncommon Files |
| .QVH | Uncommon Files |
| .QVI | Uncommon Files |
| .QVJ | Uncommon Files |
| .QVK | Uncommon Files |
| .QVL | Uncommon Files |
| .QVM | System Files |
| .QVN | Uncommon Files |
| .QVO | Uncommon Files |
| .QVP | Data Files |
| .QVQ | Uncommon Files |
| .QVR | Uncommon Files |
| .QVS | Uncommon Files |
| .QVT | Settings Files |
| .QVU | Uncommon Files |
| .QVV | Uncommon Files |
| .QVW | Data Files |
| .QVX | Uncommon Files |
| .QVY | Uncommon Files |
| .QVZ | Uncommon Files |
| .QW | Uncommon Files |
| .QW0 | Uncommon Files |
| .QW1 | Uncommon Files |
| .QW2 | Uncommon Files |
| .QW3 | Uncommon Files |
