<s>
ClickOnce	B-Application
is	O
a	O
component	O
of	O
Microsoft	O
.NET	O
Framework	O
2.0	O
and	O
later	O
,	O
and	O
supports	O
deploying	O
applications	O
made	O
with	O
Windows	B-Application
Forms	I-Application
or	O
Windows	B-Device
Presentation	I-Device
Foundation	I-Device
.	O
</s>
<s>
It	O
is	O
similar	O
to	O
Java	B-Application
Web	I-Application
Start	I-Application
for	O
the	O
Java	B-Device
Platform	I-Device
or	O
Zero	B-Application
Install	I-Application
for	O
Linux	B-Application
.	O
</s>
<s>
The	O
core	O
principle	O
of	O
ClickOnce	B-Application
is	O
to	O
ease	O
the	O
deployment	O
of	O
Windows	O
applications	O
.	O
</s>
<s>
In	O
addition	O
,	O
ClickOnce	B-Application
aims	O
to	O
solve	O
three	O
other	O
problems	O
with	O
conventional	O
deployment	O
models	O
:	O
the	O
difficulty	O
in	O
updating	O
a	O
deployed	O
application	O
,	O
the	O
impact	O
of	O
an	O
application	O
on	O
the	O
user	O
's	O
computer	O
,	O
and	O
the	O
need	O
for	O
administrator	O
permissions	O
to	O
install	O
applications	O
.	O
</s>
<s>
ClickOnce-deployed	O
applications	O
are	O
considered	O
"	O
low	O
impact	O
"	O
,	O
in	O
that	O
they	O
are	O
installed	O
per	O
user	O
,	O
not	O
per	O
machine	O
.	O
</s>
<s>
Each	O
ClickOnce	B-Application
application	O
is	O
isolated	O
from	O
the	O
others	O
.	O
</s>
<s>
This	O
means	O
one	O
ClickOnce	B-Application
application	O
is	O
not	O
able	O
to	O
"	O
break	O
"	O
another	O
.	O
</s>
<s>
ClickOnce	B-Application
employs	O
Code	O
Access	O
Security	O
(	O
CAS	O
)	O
to	O
prevent	O
system	O
functions	O
being	O
called	O
by	O
a	O
ClickOnce	B-Application
application	O
from	O
the	O
web	O
,	O
ensuring	O
the	O
security	O
of	O
data	O
and	O
the	O
client	O
system	O
in	O
general	O
.	O
</s>
<s>
The	O
ClickOnce	B-Application
model	O
supports	O
both	O
installed	O
applications	O
(	O
akin	O
to	O
conventional	O
Windows	O
applications	O
with	O
Start	O
Menu	O
integration	O
)	O
and	O
online	O
applications	O
(	O
browser-hosted	O
applications	O
that	O
are	O
not	O
installed	O
,	O
only	O
run	O
and	O
cached	O
)	O
.	O
</s>
<s>
ClickOnce	B-Application
applications	O
can	O
be	O
deployed	O
to	O
a	O
computer	O
from	O
an	O
internet	O
location	O
,	O
a	O
network	O
share	O
,	O
or	O
a	O
local	O
file	O
location	O
such	O
as	O
a	O
CD-ROM	O
.	O
</s>
<s>
The	O
ClickOnce	B-Application
deployment	O
technology	O
has	O
been	O
integrated	O
into	O
Visual	O
Studio	O
2005	O
and	O
later	O
.	O
</s>
<s>
It	O
is	O
also	O
natively	O
supported	O
by	O
MSBuild	B-Application
,	O
Microsoft	O
's	O
build	O
management	O
technology	O
.	O
</s>
<s>
A	O
ClickOnce	B-Application
deployment	O
is	O
controlled	O
through	O
the	O
use	O
of	O
two	O
XML	B-Protocol
manifest	O
files	O
:	O
a	O
deployment	O
manifest	O
and	O
an	O
application	O
manifest	O
.	O
</s>
<s>
The	O
manifests	O
are	O
in	O
the	O
same	O
XML	B-Protocol
format	O
as	O
the	O
side-by-side	O
assembly	O
implementation	O
.	O
</s>
<s>
The	O
deployment	O
manifest	O
( *	O
.application	B-Application
file	O
)	O
describes	O
the	O
deployment	O
model	O
:	O
the	O
current	O
version	O
,	O
update	O
behavior	O
,	O
publisher	O
identity	O
along	O
with	O
a	O
digital	O
signature	O
;	O
this	O
manifest	O
is	O
intended	O
to	O
be	O
authored	O
by	O
administrators	O
who	O
handle	O
deployment	O
.	O
</s>
<s>
In	O
order	O
to	O
launch	O
a	O
ClickOnce	B-Application
application	O
,	O
a	O
user	O
clicks	O
on	O
its	O
deployment	O
manifest	O
file	O
.	O
</s>
<s>
Currently	O
,	O
ClickOnce	B-Application
will	O
only	O
launch	O
if	O
the	O
URL	O
to	O
the	O
deployment	O
manifest	O
is	O
opened	O
using	O
Internet	O
Explorer	O
or	O
Edge	O
.	O
</s>
<s>
ClickOnce	B-Application
applications	O
can	O
be	O
self-updating	O
.	O
</s>
<s>
Depending	O
on	O
the	O
installation	O
type	O
,	O
ClickOnce	B-Application
presents	O
several	O
update	O
options	O
.	O
</s>
<s>
ClickOnce	B-Application
also	O
exposes	O
programmatic	O
APIs	O
to	O
customize	O
update	O
behavior	O
.	O
</s>
<s>
Native	O
support	O
for	O
ClickOnce	B-Application
applications	O
is	O
only	O
available	O
via	O
Internet	O
Explorer	O
and	O
Edge	O
.	O
</s>
<s>
With	O
the	O
release	O
of	O
.NET	O
Framework	O
3.5	O
with	O
Service	O
Pack	O
1	O
,	O
Microsoft	O
included	O
a	O
Firefox	O
add-on	O
called	O
.NET	O
Framework	O
Assistant	O
that	O
enabled	O
ClickOnce	B-Application
support	O
in	O
Firefox	O
3	O
and	O
later	O
.	O
</s>
<s>
Other	O
browsers	O
may	O
have	O
third-party	O
extensions	O
available	O
that	O
add	O
ClickOnce	B-Application
support	O
such	O
as	O
Menarva	O
Ltd	O
's	O
ClickOnce	B-Application
for	O
Google	O
Chrome	O
.	O
</s>
