Drive Letter Access

History

DLA was originally developed by VERITAS Software and later sold to Sonic Solutions in 2002. It was common as it was shipped with a majority of CD and DVD recording drives, where DLA came as a custom OEM version for the branded drive. Also, most PC systems from Dell, HP, IBM, Sony and Toshiba came with DLA pre-installed. An OEM version was often available for download for the specific computer system.

With Windows Vista support for DLA was either dropped or it was replaced by a similar product, like Drag-to-Disc.

Technology

To use an optical medium such as a CD-R, CD-RW, DVD±R or DVD±RW just like a floppy drive it is necessary to utilize a technique called packet writing. After formatting the optical media it is then possible to write data in small packets, hence the name “packet writing.” The optical drive unit has to support the ability to write in small units, which all modern CD and DVD recording drives do. This way it is possible to save files onto optical media, as well as change, rename or delete them, or copy files separately onto the media.

Without packet writing, optical media like the above-mentioned would have to be written on in one big block, like Disc At Once (DAO), Session At Once (SAO) and Track At Once (TAO), because these media types normally do not support sectors. After formatting with packet writing the medium is sectored in blocks that can be written to individually. The preferred file system is the Universal Disk Format (UDF) in versions from 1.50 onward, which is also used by DLA.

Packet writing is not required for writing DVD-RAM. DVD-RAM media are already sectored (which can be seen when looking at the surface of an empty DVD-RAM disc) and the hardware logic of DVD-RAM capable drives supports sectored read/write operations as required by the DVD-RAM standard. However, for Windows up to 2000, DLA will also add support for DVD-RAM together with the UDF file system, for Windows XP DLA will only add the UDF support.
DLA also supports the Mount Rainier standard with MRW capable drives. For Windows up to XP DLA will provide this functionality as well as the UDF support.

Windows XP is the first Windows operating system to support DVD-RAM. Windows Vista is the first Windows operating system to support full UDF functionality (UDF up to version 2.50, full support meaning read and write operations) and Mount Rainier.

Versions

DLA is available only for Microsoft Windows operating systems and only in the English language.

Note: Most OEM versions officially support only Windows 2000 and XP; however, DLA itself also runs on older versions of Windows, like Windows 98 Second Edition and Windows Me, as well as Windows NT 4.0.

A patch is required for Windows Vista compatibility, but it only works on the retail or trial version. The one exception is the Dell OEM version, but instead of patching DLA it will simply install Drag-to-Disc as a replacement.

Known problems

1. Launch Windows Explorer or open its My Computer component.
2. Select the RW drive.
3. Right click on the drive.
4. Click "Properties"
5. Click the "Hardware" tab
6. Deselect (uncheck) Use with DLA