<s>
Microsoft	B-Application
Anti-Virus	I-Application
(	O
MSAV	B-Application
)	O
is	O
an	O
antivirus	B-Application
program	I-Application
introduced	O
by	O
Microsoft	O
for	O
its	O
MS-DOS	B-Application
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
and	O
last	O
appeared	O
in	O
MS-DOS	B-Application
6.22	O
.	O
</s>
<s>
The	O
first	O
version	O
of	O
the	O
antivirus	B-Application
program	I-Application
was	O
basic	O
,	O
had	O
no	O
inbuilt	O
update	O
facility	O
(	O
updates	O
had	O
to	O
be	O
obtained	O
from	O
a	O
BBS	O
and	O
manually	O
installed	O
by	O
the	O
user	O
)	O
and	O
could	O
scan	O
for	O
1,234	O
different	O
viruses	O
.	O
</s>
<s>
Microsoft	B-Application
Anti-Virus	I-Application
for	I-Application
Windows	I-Application
(	O
MWAV	B-Application
)	O
,	O
included	O
as	O
part	O
of	O
the	O
package	O
,	O
was	O
a	O
front	O
end	O
that	O
allowed	O
MSAV	B-Application
to	O
run	O
properly	O
on	O
Windows	B-Application
3.1x	I-Application
.	O
</s>
<s>
In	O
2009	O
,	O
Microsoft	O
launched	O
an	O
in-house	O
antivirus	B-Application
solution	O
named	O
Microsoft	B-Application
Security	I-Application
Essentials	I-Application
,	O
which	O
later	O
was	O
phased	O
out	O
in	O
favor	O
of	O
Microsoft	B-Application
Defender	I-Application
.	O
</s>
<s>
Microsoft	B-Application
Anti-Virus	I-Application
was	O
supplied	O
by	O
Central	O
Point	O
Software	O
Inc	O
.	O
(	O
later	O
acquired	O
by	O
Symantec	O
in	O
1994	O
and	O
integrated	O
into	O
Symantec	O
's	O
Norton	B-Application
AntiVirus	I-Application
product	O
)	O
and	O
was	O
a	O
stripped-down	O
version	O
of	O
the	O
Central	O
Point	O
Anti-Virus	B-Application
(	O
CPAV	O
)	O
product	O
which	O
Central	O
Point	O
Software	O
Inc.	O
,	O
had	O
licensed	O
from	O
Carmel	O
Software	O
Engineering	O
in	O
Haifa	O
,	O
Israel	O
.	O
</s>
<s>
Carmel	O
Software	O
sold	O
the	O
product	O
as	O
Turbo	O
Anti-Virus	B-Application
both	O
domestically	O
and	O
abroad	O
.	O
</s>
<s>
Microsoft	B-Application
Anti-Virus	I-Application
for	I-Application
Windows	I-Application
was	O
also	O
provided	O
by	O
Central	O
Point	O
Software	O
.	O
</s>
<s>
MSAV	B-Application
featured	O
the	O
"	O
Detect	O
and	O
Clean	O
"	O
strategy	O
and	O
the	O
detection	O
of	O
boot	O
sector	O
and	O
Trojan	O
horse-type	O
viruses	O
(	O
which	O
were	O
typical	O
virus	O
problems	O
at	O
that	O
time	O
)	O
.	O
</s>
<s>
The	O
program	O
also	O
had	O
an	O
anti-stealth	O
and	O
check	B-Algorithm
sum	I-Algorithm
feature	O
that	O
could	O
be	O
used	O
to	O
detect	O
any	O
changes	O
in	O
normal	O
files	O
.	O
</s>
<s>
The	O
final	O
update	O
of	O
MSAV	B-Application
was	O
released	O
in	O
June	O
1996	O
by	O
Symantec	O
.	O
</s>
<s>
VSafe	O
is	O
a	O
terminate	O
and	O
stay	O
resident	O
component	O
of	O
MSAV	B-Application
that	O
provided	O
real-time	O
virus	B-Application
protection	I-Application
.	O
</s>
