MANILA, Philippines – Apple computer users with external drives may want to hold off on updating to OS X Mavericks or, if you’ve already gotten the latest version of Apple’s operating system, avoid using your external drives on those computers for a bit.

The issue being reported is that using certain types of external drives or eSATA cards with Mavericks may result in the loss of data on those external storage devices.

According to a report from InfoWorld, Western Digital sent an email to registered customers over the weekend warning against using Western Digital drives and external drives from other makers on machines running OS X Mavericks (Mac OS 10.9).

ZDNet also has its own report, citing Mavericks issues with FirmTek’s eSATA ExpressCards and Promise Technology’s Thunderbolt and Pegasus R4 arrays.

Western Digital released the following edited post on its community forums, dated November 1:

“There are reports of Western Digital and other external HDD products experiencing data loss when updating to Apple’s OS X Mavericks (10.9). Western Digital is urgently investigating these reports and the possible connection to the WD Drive Manager, WD Raid Manager and WD SmartWare software applications.

Until the issue is understood and the cause identified, WD strongly urges our customers to uninstall these software applications on their systems before updating to OS X Mavericks (10.9), or delay upgrading. If you have already upgraded to Mavericks, WD recommends that you remove these applications and restart your computer. WD has removed these software applications from our web site solely as a precaution as we investigate this issue.

If you have already upgraded to Mavericks and are experiencing difficulty in accessing your external hard drive, please do not save anything to the drive, disconnect the drive from your computer, and contact Western Digital Customer Service at http://support.wdc.com/country/ for further assistance.”

A related entry on the thread also details steps to remove Western Digital’s WD SmartWare from the Mac. The suggested workaround by Western Digital’s support staff should allow users to access the drive without destroying any data.

Mac users running OS X Mavericks may wish to see if their external hard drives are affected by doing a search for it on the Apple’s OS X Mavericks discussions page. – Rappler.com