What is cross-linked file?
MS-DOS organizes the disk's data area into sections called clusters or allocation units. Each file has its own directory entry, which includes the file name, size, attribute information, date, time, and the cluster where the start of the file is stored.
The file allocation table (FAT) includes an entry for each cluster. Each cluster's entry includes either a code specifying that it is the last cluster in the file, or the number of the next cluster used by the file. Clusters can also be marked unusable, which CHKDSK reports as bad sectors.
When the computer tries to save data to the hard drive in a place where a file already exists, the two files become cross-linked. When this occurs, data from both files share the same sector on the hard drive causing both to become corrupt. In some cases, one of the cross-linked files can be saved, but often both must be deleted.
For example, suppose you have two files, each 512 bytes in size. Each file requires one cluster. If both files are marked as being located in cluster 5, then cluster 5 probably contains the file with the later date. You can confirm this by looking at it (if it's a data file) or running it (if it's a program).
Cross-linked files are generally created when the computer is improperly shut down or an application abnormally aborts.
How to fix cross-linked files?
The only way to fix the FAT in this case is to delete BOTH files. When you delete the file, each cluster assigned to that file is marked "free to be used." If only one file is deleted, the cluster on which the cross-link occurred is marked unused, but the file system still shows that cluster as belonging to the "good" file. This causes another error (for example, CHKDSK may report a file allocation error, size adjusted or file allocation error, or file truncated). You also lose access to the file from the part that was stored in the beginning of the cross-linked cluster to the end of the file.
MS-DOS should be able to make a copy of both files (although one will probably be corrupt). If you don't want to delete both files, copy them to a floppy disk or another subdirectory before deleting them.
You can use windows' scandisk utility to have your hard drive scanned and fixed.
