Notes about the T$M file extension:
To open this file type, a required software must be installed. Without it you only see a Windows message "The following file cannot be opened
" (Windows 7) or "How do you want to open this file?
" (Windows 10) if you double-click the file. There click on "More apps"
and choose a suitable software to view such files on your PC or from email attachments.
The T$M file type is primarily associated with 'AVG' by AVG Technologies. AVG is anti-virus software that uses the following technologies to detect computer viruses: Scanning - searching for character strings that are characteristic of a given virus; Heuristic analysis - dynamic emulation of the scanned objectís instructions in a virtual computer environment; and Generic detection - detection of instructions characteristic of the given
virus/group of viruses. When AVG encounters a locked or corrupted file it must scan it copies this file to a temporary directory with this file extension. Normally, you would not see these files as they are deleted automatically but some program versions left them after a scheduled scan. This problem was supposed to be fixed in program versions released after March 2007. If you are still seeing the behavior of mysteriously appearing .T$M files in a temporary directory update your version of AVG. See the Forum thread for more details. A special thanks to user MarkA for doing the necessary research to pin this down.