Editing BIOS (section)

=== {{Anchor|SLIC}}Identification ===
Some BIOSes contain a software licensing description table (SLIC), a digital signature placed inside the BIOS by the [[original equipment manufacturer]] (OEM), for example [[Dell]]. The SLIC is inserted into the ACPI data table and contains no active code.<ref name="guytechie-2010225">{{cite web
 |url         = http://www.guytechie.com/articles/2010/2/25/how-slp-and-slic-works.html
 |title       = How SLP and SLIC Works
 |date        = 2010-02-25
 |access-date = 2015-02-03
 |website     = guytechie.com
 |url-status  = live
 |archive-url = https://web.archive.org/web/20150203135933/http://www.guytechie.com/articles/2010/2/25/how-slp-and-slic-works.html
 |archive-date = 2015-02-03
 }}</ref><ref>{{cite web
 |url         = http://www.congatec.com/fileadmin/user_upload/Documents/Application_Notes/AN21_Add_OEM_ACPI_SLIC_Table.pdf
 |title       = Create and add an OEM ACPI SLIC table module to a congatec BIOS
 |date        = 2011-06-16
 |access-date = 2015-02-03
 |website     = congatec.com
 |url-status  = live
 |archive-url = https://web.archive.org/web/20140802014113/http://www.congatec.com/fileadmin/user_upload/Documents/Application_Notes/AN21_Add_OEM_ACPI_SLIC_Table.pdf
 |archive-date = 2014-08-02
 }}</ref>

Computer manufacturers that distribute OEM versions of Microsoft Windows and Microsoft application software can use the SLIC to authenticate licensing to the OEM Windows Installation disk and system [[recovery disc]] containing Windows software. Systems with a SLIC can be preactivated with an OEM product key, and they verify an XML formatted OEM certificate against the SLIC in the BIOS as a means of self-activating (see [[System Locked Preinstallation]], SLP). If a user performs a fresh install of Windows, they will need to have possession of both the OEM key (either SLP or COA) and the digital certificate for their SLIC in order to bypass activation.<ref name="guytechie-2010225" /> This can be achieved if the user performs a restore using a pre-customised image provided by the OEM. Power users can copy the necessary certificate files from the OEM image, decode the SLP product key, then perform SLP activation manually.