  In 2000, Hwang and Li proposed a remote user authentication scheme using
smart cards to solve the problems of Lamport scheme. Later, Chan- Chang, Shen-
Lin- Hwang and then Chang-Hwang pointed out some attacks on Hwang &#8211;
Li&#8217;s scheme. In 2003, Shen, Lin and Hwang also proposed a modified scheme
to remove these attacks. In the same year, Leung-Cheng-Fong-Chan showed that
modified scheme proposed by Shen-Lin-Hwang is still insecure. In 2004, Awasthi
and Lal enhanced Shen-Lin-Hwang&#8217;s scheme to overcome its security
pitfalls. This paper analyses that the user U/smart card does not provide
complete information for the execution and proper running of the login phase of
the Awasthi- Lal&#8217;s scheme. Furthermore, this paper also modifies the
Awasthi- Lal&#8217;s scheme for the proper functioning.
