The following is VERBATIM from AppleLink. I have no further info.
Contact your dealer for new software.
**************** ATTENTION MACINTOSH SE USERS ****************
JUNE 10, 1987
THIS ALERT SUPERSEDES AND REPLACES THE PREVIOUS ALERT (JUNE 4) CONCERNING
PROBLEMS WITH MACINTOSH SE HARD DRIVE SYSTEMS.
It was reported last week that version 1.3 of HD SC Setup would resolve
potential hard disk initialization failures, and it does. However, another
problem has been discovered when HD SC Setup Version 1.3 is used to initialize
the disk. This problem, a recalibration problem, may in rare cases cause a
loss of data.
The Macintosh SE production units which MIGHT experience this are serial
numbers which begin with F721, F722, F723. (Previously reported as only F721).
The field fix for this is to use Version 1.4 HD SC Setup. This software is
available the following ways:
1) Special direct dealer mailing to be sent out June 15
2) Apple Programs bulletin board on AppleLink, Software Updates
System Software: System 4.1, Finder 5.5
Utilities Disk Version 2.0
Apple HD SC Setup Version 1.4
SPECIAL NOTE: Production units shipped from the factory with serial numbers
F724 and greater are okay and can be initialized with either HD SC Set Up 1.3
or 1.4. The actual cause of this field concern dealt with a particular
configuration of the hard drive and system software, which occurred for F721,
F722, F723 only; neither hardware nor software alone was the problem.
If servicing is performed on a Macintosh SE hard disk system, the hard disk
must either be updated or re-initialized with HD SC Setup 1.4. HD SC Set Up
1.4 will be included in production units shipped from the factory in early
July. It is recommended that customers upgrade to HD SC Set Up 1.4 to ensure
compatibility with all hardware configurations.
If you have questions, please contact your Apple representative.