FileInfo.com - The File Extensions Resource

.TPM File Extension

File Type 1	Trusted Platform Module Password File (Most common)
File Format	File
Common?	No
File Description	Saved password used for securing data with the Trusted Platform Module; saved in an XML format and should be stored in a safe location; used by the Microsoft's BitLocker Drive Encryption, along with the Encrypting File System (EFS). BitLocker is included with Microsoft's Data Encryption Toolkit.
Program(s) that open tpm files	Windows: Microsoft BitLocker

File Type 2	Transformation Parameters Model File
File Format	Proprietary File
Common?	No
File Description	Contains metadata that describes how to transform a UML (Unified Modeling Language) file into EGL (Enterprise Generation Language) code; enables graphical modeling of complex applications with IBM Rational software.
Program(s) that open tpm files	WIndows: IBM Rational Software Architect

Information from FileInfo.com - The File Extensions Resource.
http://www.fileinfo.com/extension/tpm