A file with .adp extension provides connection to a Microsoft SQL Server database. Such files do not contain actual tables or database elements. ADP files can be created with Access 2007 and 2010 and opened in Access 365. ADP File Format has settings for Access to connect to a SQL Server database.
To open an adp file, select your operating system. Then download and install an appropriate program from the list. For desktop computers, 2 programs are available for Windows to open adp files. ADP files are commonly called Access Data Projects. In Access 2000, Microsoft added ability for users to create Access Data Projects. This allowed connecting to, opening, and editing a SQL Server database.
Microsoft Access