Flash Memory Maintenance and Troubleshooting
 flash memory has a life span usually measured in millions of read-writes but it can also suffer from the same errors that a magnetic disk can experience. i have a type one compact flash card that i use with the memplug adapter for a visor. after a few years, the card/adapter combo showed increasing problems until it did not work at all. i found helpful info on some digital photography sites. with a read/writer connented to a pc it is possible to run utilities (in my case scan disk and defragmenter) on the card just like a hard drive. this fixed my card without affecting the data and now it even works much faster (like new). this may be considered a routine practice to combat degradation of performance as well.