<s>
RocketMail	B-Application
was	O
one	O
of	O
the	O
first	O
major	O
free	O
webmail	B-Protocol
services	O
.	O
</s>
<s>
The	O
service	O
was	O
originally	O
a	O
product	O
of	O
Four11	B-Application
Corporation	I-Application
.	O
</s>
<s>
For	O
a	O
brief	O
time	O
,	O
RocketMail	B-Application
battled	O
with	O
Hotmail	B-Operating_System
for	O
the	O
number-one	O
spot	O
among	O
free	O
webmail	B-Protocol
services	O
.	O
</s>
<s>
Four11	B-Application
,	O
including	O
RocketMail	B-Application
,	O
was	O
acquired	O
by	O
Yahoo	B-Application
!	I-Application
</s>
<s>
Yahoo	B-Application
!	I-Application
</s>
<s>
assimilated	O
the	O
RocketMail	B-Application
engine	O
.	O
</s>
<s>
Yahoo	B-Application
!	I-Application
</s>
<s>
Mail	O
was	O
essentially	O
the	O
old	O
RocketMail	B-Application
Webmail	B-Protocol
system	O
.	O
</s>
<s>
At	O
the	O
time	O
of	O
the	O
transition	O
,	O
RocketMail	B-Application
users	O
could	O
either	O
choose	O
a	O
Yahoo	B-Application
!	I-Application
</s>
<s>
ID	O
,	O
since	O
they	O
were	O
not	O
guaranteed	O
the	O
availability	O
of	O
their	O
RocketMail	B-Application
ID	O
on	O
Yahoo	O
!,	O
or	O
could	O
use	O
username.rm	O
as	O
their	O
Yahoo	B-Application
!	I-Application
</s>
<s>
Thus	O
,	O
they	O
were	O
able	O
to	O
keep	O
their	O
rocketmail.com	O
address	O
and	O
receive	O
the	O
same	O
services	O
as	O
all	O
Yahoo	B-Application
!	I-Application
</s>
<s>
On	O
19	O
June	O
2008	O
,	O
Yahoo	B-Application
!	I-Application
</s>
<s>
started	O
the	O
RocketMail	B-Application
brand	O
again	O
by	O
allowing	O
new	O
users	O
to	O
sign	O
up	O
for	O
accounts	O
under	O
the	O
rocketmail.com	O
domain	O
,	O
which	O
had	O
not	O
been	O
possible	O
since	O
its	O
acquisition	O
of	O
Four11	B-Application
Corporation	I-Application
.	O
</s>
<s>
In	O
April	O
2013	O
,	O
Yahoo	B-Application
!	I-Application
</s>
<s>
closed	O
support	O
for	O
creating	O
new	O
RocketMail	B-Application
email	O
addresses	O
;	O
existing	O
RocketMail	B-Application
accounts	O
were	O
not	O
affected	O
.	O
</s>
