How to open .letter file format?

The probably reason why you are at this website is a problem with opening .letter file. The full name of the file is Undeliverable Mail File. If the double-click on the file’s icon shows you a message that additional programs are needed to open the file, you’ll find the list of helpful programs in the bottom of the page.

.letter file extension (Undeliverable Mail File)

Category Developer/Producer File description Popularity
Misc Files N/A Undeliverable Mail File
RateRateRate
Programs using this file extension: .letter
ADS OS Software
Windows
Windows
  • Sendmail
MAC OS
MAC
  • Sendmail
Linux
Linux
  • Sendmail


The file extension .letter can be used by another programs. If you have some useful information about .letter file type that may help other users HowOpen.org, please send them to us and we’ll update our database.

Visiting our website you are probably asking yourself:
  • What application can open .letter file?
  • How to open .letter file?
  • What is .letter file?
  • How can I convert .letter file?
  • Where can I find informations about .letter file extension? (for example on the File Extension website)
We hope we have given you enough informations about this file type. Otherwise you can search some informations about .letter extension on Wikipedia.org.