This problem is found via Winqual.
Some OEM vendors (n this case) Dell embed MySQL (and actually more, something like WAMP) with their own tools preinstalled on new computers. Since we do not know OEM applications well enough, and do not trust users to know what they do, we should exclude OEM-specific instances from the list offered by upgrade wizard (it automatically starts whenever a service running MySQL is found)
Winqual reported several crashes on Dell machines, while running upgrade from 5.0.45 (preinstalled) to 5.3.5.
What exactly the application does is not clear, the service is named dls-db, has display name RemoteDB, and is configued to run as
C:\Program Files\Common Files\Dell\MySQL\bin\mysqld.exe
--defaults-file=C:\Program Files\Common Files\Dell\MySQL\my.ini dsl-db
The only known thing is that it belongs somehow to Dell specific systems.
Why crashes happen, is a subject for another report . the purpose of this bug report is different: we should not offer to upgrade OEM specific MySQL installations via UpgradeWizard GUI.