| Extension | File Description |
| .BLI | Uncommon Files |
| .BLINK | Uncommon Files |
| .BLJ | Uncommon Files |
| .BLK | CAD Files |
| .BLL | Uncommon Files |
| .BLM | Uncommon Files |
| .BLN | Data Files |
| .BLO | Uncommon Files |
| .BLOB | Settings Files |
| .BLOCK | Uncommon Files |
| .BLOCKS | Uncommon Files |
| .BLORB | Game Files |
| .BLOSSOMS | Uncommon Files |
| .BLP | Game Files |
| .BLQ | Uncommon Files |
| .BLR | Uncommon Files |
| .BLS | Game Files |
| .BLT | Settings Files |
| .BLU | Plugin Files |
| .BLUE | Uncommon Files |
| .BLUEBERRY | Uncommon Files |
| .BLUEESMERA | Uncommon Files |
| .BLUEMONDAY | Uncommon Files |
| .BLURB | Uncommon Files |
| .BLV | Uncommon Files |
| .BLW | Settings Files |
| .BLX | Uncommon Files |
| .BLY | Uncommon Files |
| .BLZ | Game Files |
| .BM | Uncommon Files |
| .BM$ | Uncommon Files |
| .BM0 | Uncommon Files |
| .BM1 | Uncommon Files |
| .BM2 | Data Files |
| .BM3 | Uncommon Files |
| .BM4 | Uncommon Files |
| .BM5 | Uncommon Files |
| .BM6 | Uncommon Files |
| .BM7 | Uncommon Files |
| .BM8 | Uncommon Files |
| .BM9 | Uncommon Files |
| .BMA | Uncommon Files |
| .BMAP | Uncommon Files |
| .BMB | Uncommon Files |
| .BMC | Raster Image Files |
| .BMD | Game Files |
| .BME | Game Files |
| .BMF | Raster Image Files |
| .BMG | Uncommon Files |
| .BMH | Uncommon Files |
| .BMHTML | Uncommon Files |
| .BMI | Plugin Files |
| .BMJ | Uncommon Files |
| .BMK | Misc Files |
| .BML | Web Files |
| .BMM | Uncommon Files |
| .BMN | Uncommon Files |
| .BMO | Uncommon Files |
| .BMP | Raster Image Files |
| .BMP24 | Uncommon Files |
| .BMPENX | Uncommon Files |
| .BMQ | Uncommon Files |
| .BMR | Uncommon Files |
| .BMS | Data Files |
| .BMT | Uncommon Files |
| .BMTP | Uncommon Files |
| .BMU | Uncommon Files |
| .BMV | Uncommon Files |
| .BMW | Uncommon Files |
| .BMX | Raster Image Files |
| .BMY | Uncommon Files |
| .BMZ | Raster Image Files |
| .BM_ | Uncommon Files |
| .BN | Uncommon Files |
| .BN0 | Uncommon Files |
| Extension | File Description |
| .BN1 | Uncommon Files |
| .BN2 | Uncommon Files |
| .BN3 | Uncommon Files |
| .BN4 | Uncommon Files |
| .BN5 | Uncommon Files |
| .BN6 | Uncommon Files |
| .BN7 | Uncommon Files |
| .BN8 | Uncommon Files |
| .BN9 | Uncommon Files |
| .BNA | Uncommon Files |
| .BNB | Uncommon Files |
| .BNC | Uncommon Files |
| .BND | Misc Files |
| .BNE | Uncommon Files |
| .BNF | Uncommon Files |
| .BNG | Game Files |
| .BNH | Uncommon Files |
| .BNI | Uncommon Files |
| .BNJ | Uncommon Files |
| .BNK | Game Files |
| .BNL | Uncommon Files |
| .BNM | Uncommon Files |
| .BNN | Uncommon Files |
| .BNO | Uncommon Files |
| .BNP | Uncommon Files |
| .BNQ | Uncommon Files |
| .BNR | Uncommon Files |
| .BNS | Uncommon Files |
| .BNSKIN | Uncommon Files |
| .BNT | Uncommon Files |
| .BNU | Uncommon Files |
| .BNV | Uncommon Files |
| .BNW | Uncommon Files |
| .BNX | Uncommon Files |
| .BNY | Uncommon Files |
| .BNZ | Uncommon Files |
| .BN_ | Uncommon Files |
| .BO0 | Uncommon Files |
| .BO1 | Uncommon Files |
| .BO2 | Uncommon Files |
| .BO3 | Uncommon Files |
| .BO4 | Uncommon Files |
| .BO5 | Uncommon Files |
| .BO6 | Uncommon Files |
| .BO7 | Uncommon Files |
| .BO8 | Uncommon Files |
| .BO9 | Uncommon Files |
| .BOA | Uncommon Files |
| .BOARD | Uncommon Files |
| .BOB | Uncommon Files |
| .BOC | Uncommon Files |
| .BOCHSRC | Uncommon Files |
| .BOD | Uncommon Files |
| .BOE | Uncommon Files |
| .BOF | Uncommon Files |
| .BOG | Uncommon Files |
| .BOH | Uncommon Files |
| .BOI | Uncommon Files |
| .BOJ | Uncommon Files |
| .BOK | Data Files |
| .BOL | Uncommon Files |
| .BOLD | Uncommon Files |
| .BOLD6 | Uncommon Files |
| .BOLF6 | Uncommon Files |
| .BOM | System Files |
| .BOMBER | Uncommon Files |
| .BON | Uncommon Files |
| .BONES | Uncommon Files |
| .BONGO | Uncommon Files |
| .BONK | Uncommon Files |
| .BOO | Compressed Files |
| .BOOK | Data Files |
| .BOOKS | Uncommon Files |
| .BOOST | Uncommon Files |
| .BOOT | Settings Files |
