NWA-PCUG Newsletter Article, October 2002
Are You Having "Buffer Underrun" Errors
With Your CD Burner?

by Ira Wilsker
(click to email author)

During one of my recent radio shows (KLVI 560AM, Tuesdays 6-7pm, Saturdays, 1-4pm), I received many calls asking how to overcome the infamous "Buffer Underrun" error when writing to CD-R discs. While many of the newer CD-RW drives have built-in protection to prevent this error, the vast majority of CD-RW drives in use are subject to this most frustrating disc-ruining error.

According to several of the CD-RW drive manufacturers' websites, as well as the websites of several of the major CD burning software publishers, this error is the single most common problem encountered by users when creating CD-R discs. A buffer underrun occurs when the buffer or memory cache (temporary storage) either built in the CD-RW drive, or supplied by the CD burning software, can not keep up with the data being written to the CD disc.

Normally the buffer receives data from the computer, and parcels it out to the disc, the buffer supposedly holding enough data to feed and write smoothly to the CD-R disc as it is also receiving data from the computer. Ideally, the data stream should be smooth and continuous. If, for any of many reasons, the buffer does not have the requisite amount of data available, it is possible that a buffer underrun error may be created. Common causes of this error are inadequate system performance (not enough memory, slow processor, hard drive problems, too many programs loaded and running), and low quality or defective CD-R discs.

There are several simple tasks that can be done to reduce the chance of buffer underrun errors due to poor system performance.

Most CD burning software indicates the maximum speed that the CD can write, typically in the format of "8x" or "10x" on a pull down menu. By selecting a writing speed one or two levels lower than the maximum, the error often disappears. Running both the Windows integral Scandisk and Defrag programs, or similar third party utilities, can possibly ensure that the hard drive is not the culprit causing the errors. Most of the CD burning software uses that hard drive as intermediate storage while the CD is being created, and the rule-of-thumb is that hard drive space of at least 150% of the amount of data being written must be readily available on the hard drive. If cluttered with obsolete data, simply cleaning the c:\windows\temp directory by deleting obsolete files can often help prevent the problem. In many older Windows computers, mostly running Windows 98 and 95, the CD drive settings may be incorrectly configured. Go to My Computer "Control Panel/System/Device Manager/click on the "+" to the left of "CDROM" to show the drive model/click on the CD drive to highlight it/click on properties/Settings/ and check both "Disconnect" and "Auto Insert Notification", and uncheck "Sync Data Transfer". On many computers, properly setting this configuration alone may be adequate to eliminate the error.

If inadequate system resources cause the problem, it may also be easily resolved without the necessity of spending money to add memory or install a faster processor. Sometimes programs that have been already exited leave kernels of code or data in memory that unnecessarily consumes resources; typically the easiest method to restore those resources is to simply reboot the computer. By simply stopping any unnecessary programs from running in the background, and not performing any other tasks while burning CDs (multitasking), system resources consisting of CPU power, memory, and other resources may be easily and quickly made available. That traditional method to stop unwanted programs that may be running is to either right click on their icon in the taskbar and click on "close", or do a CTRL-ALT- DELETE, followed by task manager on newer operating systems, and "end task" all programs running except "systray" and "explorer", before burning the CD. After the CD has been successfully created, reboot the computer in order to load antivirus software, and other desired utilities.

Another option, which may also improve general system performance, not just CD writing, is to stop unnecessary programs from loading at all during the boot "start up" sequence. Detailed instructions on how to do this for all Windows operating systems can be found by clicking on the first link on my radio show web page at http://www.mycomputershow.com. An alphabetical list of programs that may be in the startup, along with an indication of if they are necessary or unnecessary, is the second link on my website. Being connected to an "always on" broadband internet connection, such as DSL or cable can also consume resources. If the error occurs, disconnect from the net.

Another possible cause of the error may be the CD burning software itself. Most software included free with CD-RW drives is the "lite" or "limited" version lacking some of the features of the full commercial versions. Check your software publisher's website for updates to the version of software being used, as these may resolve the buffer underrun problem. Newer versions of the software, sometimes downloadable either as free upgrades, or available to registered users at a discount, may also resolve the problem. Some CD burning software better manage resources and buffers than others, and a software change may show improvement. Many of the CD software publishers offer a free trial version of their product for download; this may be a useful exercise.

The CD-R media itself can be the culprit. Newer disc technologies, often using a blue or green dye on the writable side of the disc, can usually be written to faster and more reliably than the older, and cheaper, silver dye technology. The difference in price between the better quality blank CDs, and the no-name cheap generics is often small, considering the savings in both ruined discs, and the time to create them.

By properly configuring your computer and software, the CD burning experience can be less frustrating, and more productive.

Ira Wilsker is a member of the APCUG Board of Advisors, hosts a radio show, writes a column for his local paper and is on the faculty at the Lamar institute. Email him at: ira@apcug.org .

There is no restriction against any non-profit group using the article as long as it is kept in context, with proper credit given to the author. This article is brought to you by the Editorial Committee of the Association of Personal Computer User Groups (APCUG), an International organization to which this user group belongs.

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