TeslaDecoder can decrypt all variants of TeslaCrypt including .micro, .xxx, .ttt, .mp3, and even encrypted files that were not renamed.

For older versions of TeslaCrypt TeslaDecoder will search for certain Windows registry keys, the storage.bin file, or key.dat file, and if detected, will attempt to extract your decryption key. Once a decryption key is extracted it will allow you to decrypt all the files in a particular folder or all files on a computer. On some computer's the decryption key has been stripped from the data files and TeslaDecoder will be unable to help you recover your files.

For newer versions of TeslaCrypt you need to read and follow the instructions.

Either way, please see the readme or instructions in the program.