Allocation Discrepancy: Page is allocated but not linked; check the following pages and ids: allocation pg#=%ld extent id=%ld logical pg#=%ld object id on extent=%ld (object name = %.*s) indid on extent=%ld
This error indicates that a page is marked as allocated to an object, although it is not being used. One page of disk space cannot be used, however, until the error is corrected, so each 2540 error means the loss of one blank data page of disk space. The table data is not corrupt and no data loss is associated with this error.
A few 2540 errors are no cause for concern. If many of these errors occur, however, the amount of disk space lost could be significant.
You can usually correct error 2540 by running DBCC FIX_AL, as follows:
dbcc fix_al (database_name)
Important Before running DBCC FIX_AL, run DBCC CHECKDB to be sure there are no other related problems.
If this doesn't work, restore the database from a known clean backup.
If the problem persists, contact your primary support provider. Have the output from the appropriate DBCC statements available for review.