ScanDisk storage card health monitoring and error repair for Windows Mobile

Storage cards are susceptible to errors. Over time, clusters can become corrupted, part of files can become lost, and a range of other errors can occur. You should take the time to run ScanDisk to monitor the health of your storage cards and repair any issues found, especially if the number of files and applications are growing and your system is getting old – it may save you from a whole lot of lost data in the long run.

File system errors are the number one reason for data corruption and loss of important files and data on your Windows Mobile device. Every time a program locks up or you soft reset your Windows Mobile device because an application stopped responding, there is a risk of introducing errors on your storage card. If the mobile device is interrupted while writing information on the storage card, the resulting data is often incomplete. Most often this happens because the operating system is not able to update the FAT tables or the file chains because of the lock up/soft reset. No matter what the potential cause may be, it is quite possible that lost clusters and/or chains are on your storage card. A lost cluster or chain is data that is “lost” and cannot be accessed through the file system. This can also cause random lock-ups or application errors.

If ScanDisk is not performed on a regular basis your device may become sluggish in performance. ScanDisk is one of the essential tools used to maintain performance and error-free file management.

Features:

• FAT mismatches – this is the most dangerous of file system logic problems with potential for massive data loss. The File Allocation Table tracks which data cluster follows the previous cluster within files and directories, and this information is near-impossible to deduce if it is lost. For this reason, there are two copies of the FAT, and ScanDisk detects the "mismatched FAT" problem when these differ. ScanDisk "fixes" this problem by asking the user which FAT copy is the correct one, and by overwriting the contents of the other one with it. Always backup all data on the card before attempting recovery of a mismatched FAT.

• FAT errors – occasionally the entries in the FAT can become corrupted or set to invalid values. Wizcode ScanDisk Mobile will detect and correct these sorts of problems on the fly.

• Lost clusters – virtually every storage card using the FAT file system has come across this problem. Lost clusters are clusters that are marked as being used in the FAT tables but are not linked to any directory entries. This problem is often found after a system crash, when there are data clusters chained out of free space but where there is no directory entry pointing to the cluster chain thus formed. Such files were typically opened for writing at the time the system crashed, restarted, or was switched off. Often these were temporary files that would have been deleted during shutdown anyway, but they can also be data files that were in use at the time. Wizcode ScanDisk Mobile can reconstruct the lost cluster chains and save the files in the root folder of the storage card. File names of lost cluster chains cannot be recovered so ScanDisk will use generic names like FILE0001.CHK, FILE0002.CHK etc when converting the lost cluster chains to files. Lost clusters can be optionally discarded instead of being saved, thus freeing the space they occupy on the disk.

• Invalid cluster chains – sometimes cluster chains may contain invalid values like an invalid cluster number or a missing end-of-chain marker. Wizcode ScanDisk Mobile is able to detect and fix such issues.

• Cross-linked files – on rare occasions, two or more files can end up pointing to the same data on the storage card. This is a problem since each time you use either file, you will overwrite the other one(s). Wizcode ScanDisk Mobile can effectively fix this issue by making copies of the cross-linked file chains and updating the directory entries of each cross-linked file.

• Directory entry issues – very rarely, the internal structures of files or directories can become damaged so that some entries are no longer following the "rules" for how a file or directory is supposed to be laid out. An example would be difference between the file size stored in the directory entry vs. the actual calculated size from the FAT tables, or a file that has an invalid start cluster. Sometimes files get assigned an invalid date or time by a buggy piece of software. These problems can usually be fixed by Wizcode ScanDisk Mobile.

• Folder relation errors – an example would be a directory that doesn’t have a pointer to its parent directory or to itself which can cause entire folders full of data to "disappear" from the storage card. Wizcode ScanDisk mobile is able to resolve such errors by checking the links between folders and reconstructing the missing directory entries if required.

• Bad sectors – a bad sector is a sector on a storage card that cannot be used due to permanent damage, such as physical damage to the disk particles (if using a micro-drive for example) or media wear (for flash based storage cards). Wizcode ScanDisk Mobile is able to detect such problems by attempting to access all sectors on a storage card and checking if there are any issues. In case of problems ScanDisk will attempt to get the data from the defective sectors and will move it to healthy sector. The bad sector will be marked as such in the FAT tables so it will not be used by the operating system anymore while the new sector will be marked as used if it was a part of a cluster chain.

TECHNICAL SPECIFICATIONS:

• Windows Mobile 6
• Windows Mobile 5
• Windows Mobile 2003 / Second edition

Supported screen resolutions:

• WVGA portrait (800×480)
• WVGA landscape (480×800)
• VGA portrait (640×480)
• VGA landscape (480×640)
• QVGA portrait (320×240)
• QVGA landscape (240×320)
• Square (240×240)
• Square Hi-res (480×480)

More info and download: http://www.wizcode.com/products/view/scandisk_mobile