Dear Nks2011,
E-mail communication is acceptable under the provisions of Indian Evidence Act. However, to prove that this communication has taken place or prove the authenticity of the communication is cumbersome. This cumbersomeness is for either side i.e. for employer and employee.
Therefore, before embarking on this idea, tell your legal department to check how much time it will take to prove authenticity of communication in case of litigation. Please note that the government authorities do not function as fast as click of the mouse. While litigation is not order of the day and we might have to approach the cyber cell authorities once in blue moon, but then as much time you have saved by generating the offer and appointment letters automatically, the same time will be lost in one such case.
From the HR standpoint, why it takes "long time" to send the offer letter or appointment letter? Have you measured the turnaround time to issue appointment letter and what efforts did you take to reduce it? How many appointments take place per month? What is the scope of delegation? What is the scope to delegate this activity to more than one person?
To begin with, you may start with the offer letter but may not appointment letter.
Thanks,
Dinesh Divekar
Business Mentor, Consultant and Trainer