A computer hard-drive that dies or becomes inaccessible is cause for panic and despair when your small business depends on data, but all may not be lost. How much of the data you will be able to recover depends on how carefully you respond and how much you are willing to pay.

Just because your computer can no longer read the files on a hard drive doesn't mean that the drive has stopped to function or that the files are gone. Files that the operating system needs to boot properly may have been deleted or corrupted, or a few bad areas (or sectors) of the drive could prevent the drive from being recognized by your computer.

Do-it-yourself recovery

Drives that spin up but won't boot can be installed as a second drive on a working computer. Another trick for drives that are performing erratically is to let the drive cool down or put it in the freezer, which could make the drive accessible long enough to extract the most necessary files, says Dave Methvin, chief technology officer of computer tune-up website PCPitstop.com.

If the drive sounds stuck -- known as stiction, a contraction of static and friction -- or is making scraping or rapping sounds, tapping the drive with a pen could move the drive past a bad area in some cases. But this could also do further damage, Methvin warns.

Getting outside help

Computer electronics stores such as CompUSA and Frye's as well as independent computer shops rely on disk utilities and basic hardware know-how to recover files. This may be a good choice for a small or mid-size business, depending upon the value of the stored data to the business. These companies tend to charge between $100-$300 dollars or more, depending on how fast the data needs to be recovered.

More advanced (and expensive) services should be reserved for mission-critical data. Companies such as Ontrack Data Recovery, ACS Data Recovery, or DriveSavers charge from $500 to several thousand dollars to take malfunctioning drives and their supporting electronics apart. DriveSavers offers a priority service starting at approximately $1800 where one or more engineers will work around-the-clock until data is recovered or the drive is deemed useless, says John Christopher, DriveSavers' senior data recovery engineer.

Recovering the data

Non-working drives are sent via delivery services to these data recovery experts, and the files that are recovered can be returned either online (through file transfer protocol, or FTP), or on a DVD, CD, or tape as requested. Depending on the service level, data recovery times can be one to several days, so companies should plan on temporarily functioning without the files.

Companies that infrequently backup files might be better off turning to outdated copies of files rather than hoping that the most recent copy will be found, says Arun Taneja, the founder of consulting firm the Taneja Group, of Hopkington, Mass. IT departments could retrieve older copies of files on a tape backup system in a few hours or days, Taneja says.

E-mail's saving grace

Before springing for an expensive recovery service, you may be able to retrieve recent copies of many files by mining e-mail archives. Internet-based e-mail services such as Hotmail or Gmail retain copies of e-mails and attachments that were received for a short period of time. Depending on user settings, they may retain sent files, too. Server-based e-mail systems such as Microsoft Exchange or Lotus Notes keep copies of e-mails and their attachments, as well. As a last resort, you can ask peers or clients with whom you've e-mailed if they have copies of some of your critical files. However, first consider whether the admission that you've lost valuable data will cost you their business.