Error: 400 Invalid value....

[Jaymeet]

when ever i try to new attachment and fill Data like = "Have Nice Day". After that i clicked on right symbol for saving attachment. I got an error on dialog box like : Error:400 Invalid value at 'attachment.data'(TYPE_BYTES), Base64 decoding failed for "Have Nice Day" in this given github example.

Any One can suggest me for helping or solving this problem.