<s>
Pegasus	B-Application
Mail	I-Application
is	O
a	O
proprietary	B-Application
email	B-Protocol
client	I-Protocol
developed	O
by	O
David	O
Harris	O
(	O
who	O
also	O
develops	O
the	O
Mercury	B-Application
Mail	I-Application
Transport	I-Application
System	I-Application
)	O
.	O
</s>
<s>
It	O
was	O
originally	O
released	O
in	O
1990	O
for	O
internal	O
and	O
external	O
mail	O
on	O
NetWare	B-Operating_System
networks	O
with	O
MS-DOS	B-Application
and	O
later	O
Apple	B-Device
Macintosh	I-Device
clients	O
.	O
</s>
<s>
It	O
was	O
subsequently	O
ported	O
to	O
Microsoft	B-Application
Windows	I-Application
,	O
which	O
is	O
now	O
the	O
only	O
platform	O
actively	O
supported	O
.	O
</s>
<s>
Previously	O
freeware	B-License
,	O
Pegasus	B-Application
Mail	I-Application
is	O
now	O
donationware	B-License
.	O
</s>
<s>
The	O
early	O
versions	O
of	O
Pegasus	O
were	O
installed	O
on	O
MS-DOS	B-Application
or	O
Mac	B-Device
workstations	O
on	O
a	O
Netware	B-Operating_System
network	O
,	O
and	O
supported	O
only	O
mail	O
between	O
network	O
users	O
;	O
for	O
external	O
(	O
Internet	O
)	O
the	O
Mercury	B-Application
Mail	I-Application
Transport	I-Application
System	I-Application
for	O
Netware	B-Operating_System
was	O
required	O
.	O
</s>
<s>
Pegasus	B-Application
Mail	I-Application
(	O
PMail	B-Application
)	O
is	O
suitable	O
for	O
single	O
or	O
multiple	O
users	O
on	O
stand-alone	O
computers	O
and	O
for	O
internal	O
and	O
Internet	O
mail	O
on	O
local	B-General_Concept
area	I-General_Concept
networks	I-General_Concept
.	O
</s>
<s>
Pegasus	B-Application
Mail	I-Application
has	O
minimal	O
system	O
requirements	O
compared	O
with	O
competing	O
products	O
,	O
for	O
instance	O
the	O
installed	O
program	O
(	O
excluding	O
mailboxes	O
)	O
for	O
version	O
4.52	O
requires	O
only	O
around	O
13.5	O
MB	O
of	O
hard	O
drive	O
space	O
.	O
</s>
<s>
Since	O
Pegasus	B-Application
Mail	I-Application
does	O
not	O
make	O
changes	O
to	O
the	O
Windows	B-Protocol
registry	I-Protocol
or	O
the	O
system	O
directory	O
,	O
it	O
is	O
suitable	O
as	O
a	O
portable	B-Application
application	I-Application
for	O
USB	B-Protocol
drives	O
.	O
</s>
<s>
A	O
significant	O
feature	O
of	O
the	O
Microsoft	B-Application
Windows	I-Application
version	O
of	O
Pegasus	B-Application
Mail	I-Application
is	O
that	O
users	O
have	O
the	O
choice	O
not	O
to	O
use	O
Microsoft	B-Application
Internet	I-Application
Explorer	I-Application
's	O
HTML	B-Language
layout	B-Protocol
engine	I-Protocol
when	O
displaying	O
HTML	B-Language
email	O
.	O
</s>
<s>
Malicious	O
HTML	B-Language
tends	O
to	O
be	O
highly	O
dependent	O
on	O
the	O
exact	O
target	O
application	O
and	O
OS	O
,	O
therefore	O
by	O
avoiding	O
both	O
the	O
ubiquitous	O
HTML	B-Language
renderer	O
supplied	O
with	O
Windows	O
and	O
not	O
allowing	O
automation	O
commands	O
such	O
as	O
ActiveX	B-Application
and	O
JavaScript	B-Language
to	O
execute	O
from	O
within	O
an	O
email	O
in	O
its	O
inbuilt	O
renderer	O
,	O
Pegasus	O
reduces	O
substantially	O
the	O
risk	O
of	O
infection	O
from	O
viewing	O
email	O
.	O
</s>
<s>
Pegasus	O
has	O
the	O
facility	O
,	O
not	O
provided	O
by	O
all	O
mail	B-Protocol
clients	I-Protocol
,	O
optionally	O
to	O
download	O
headers	O
only	O
,	O
allowing	O
the	O
user	O
to	O
select	O
mail	O
to	O
ignore	O
for	O
now	O
and	O
deal	O
with	O
later	O
,	O
download	O
and	O
delete	O
from	O
the	O
server	O
(	O
normal	O
mail	O
operation	O
for	O
POP3	B-Protocol
access	O
)	O
,	O
download	O
a	O
copy	O
of	O
a	O
message	O
while	O
leaving	O
it	O
on	O
the	O
server	O
,	O
or	O
delete	O
without	O
downloading	O
.	O
</s>
<s>
The	O
original	O
version	O
worked	O
with	O
Novell	B-Operating_System
NetWare	I-Operating_System
networks	O
and	O
their	O
Message	B-Application
Handling	I-Application
System	I-Application
(	O
MHS	O
)	O
mail	O
system	O
;	O
a	O
cut-down	O
MHS-only	O
version	O
called	O
FirstMail	O
was	O
bundled	O
with	O
NetWare	B-Operating_System
.	O
</s>
<s>
Early	O
versions	O
used	O
only	O
a	O
non-standard	O
format	O
for	O
mail	O
folders	O
;	O
later	O
versions	O
offer	O
the	O
standard	B-Application
Unix	I-Application
mailbox	I-Application
format	I-Application
as	O
an	O
alternative	O
to	O
the	O
Pegasus	B-Application
Mail	I-Application
format	O
.	O
</s>
<s>
Although	O
no	O
longer	O
developed	O
or	O
supported	O
,	O
older	O
versions	O
for	O
MS-DOS	B-Application
and	O
Apple	B-Device
Macintosh	I-Device
are	O
still	O
available	O
.	O
</s>
<s>
A	O
problem	O
with	O
early	O
versions	O
is	O
that	O
mail	O
was	O
stored	O
on	O
the	O
NetWare	B-Operating_System
System	O
volume	O
.	O
</s>
<s>
This	O
caused	O
problems	O
with	O
NetWare	B-Operating_System
servers	O
with	O
a	O
small	O
System	O
volume	O
and	O
larger	O
ones	O
for	O
data	O
storage	O
,	O
as	O
users	O
often	O
kept	O
many	O
large	O
messages	O
in	O
their	O
new	O
mail	O
folders	O
.	O
</s>
<s>
Pegasus	B-Application
Mail	I-Application
supports	O
the	O
POP3	B-Protocol
,	O
IMAP	B-Protocol
,	O
and	O
SMTP	B-Protocol
protocols	I-Protocol
as	O
well	O
as	O
Novell	O
's	O
MHS	O
.	O
</s>
<s>
Release	O
4.41	O
also	O
has	O
,	O
amongst	O
other	O
features	O
,	O
an	O
improved	O
HTML	B-Protocol
rendering	I-Protocol
engine	I-Protocol
,	O
better	O
support	O
for	O
special	O
character	O
encoding	O
(	O
especially	O
with	O
UTF-8	O
)	O
,	O
phishing	O
protection	O
,	O
and	O
a	O
full-fledged	O
Bayesian	B-Application
spam	I-Application
filter	I-Application
.	O
</s>
<s>
Pegasus	B-Application
Mail	I-Application
for	O
Windows	O
can	O
be	O
used	O
as	O
a	O
standalone	O
mail	B-Protocol
client	I-Protocol
using	O
POP3	B-Protocol
or	O
IMAP	B-Protocol
for	O
incoming	O
mail	O
and	O
SMTP	B-Protocol
for	O
outgoing	O
,	O
or	O
on	O
a	O
NetWare	B-Operating_System
or	O
Windows	O
network	O
in	O
conjunction	O
with	O
the	O
Mercury	B-Application
Mail	I-Application
Transport	I-Application
System	I-Application
for	O
Windows	O
or	O
NetWare	B-Operating_System
,	O
also	O
by	O
David	O
Harris	O
,	O
running	O
on	O
a	O
network	O
server	O
to	O
receive	O
mail	O
and	O
distribute	O
it	O
to	O
users	O
.	O
</s>
<s>
While	O
Pegasus	B-Application
Mail	I-Application
and	O
Mercury	B-Application
handle	O
email	O
only	O
,	O
the	O
function	O
of	O
Pegasus	B-Application
Mail	I-Application
is	O
comparable	O
to	O
Microsoft	B-Application
Outlook	I-Application
's	O
mail	O
handling	O
,	O
and	O
Mercury	B-Application
to	O
Microsoft	B-Operating_System
Exchange	I-Operating_System
Server	I-Operating_System
.	O
</s>
<s>
Pegasus	B-Application
Mail	I-Application
pioneered	O
many	O
features	O
now	O
taken	O
for	O
granted	O
with	O
other	O
email	B-Protocol
clients	I-Protocol
,	O
such	O
as	O
filtering	O
and	O
simultaneous	O
access	O
to	O
multiple	O
POP3	B-Protocol
and	O
IMAP4	B-Protocol
accounts	O
.	O
</s>
<s>
However	O
,	O
the	O
free	O
distribution	O
of	O
Microsoft	B-Application
Outlook	I-Application
Express	I-Application
or	O
later	O
email	B-Protocol
client	I-Protocol
as	O
a	O
standard	O
part	O
of	O
Microsoft	B-Application
Windows	I-Application
since	O
Windows	B-Device
98	I-Device
,	O
and	O
the	O
distribution	O
of	O
Microsoft	B-Application
Outlook	I-Application
,	O
initially	O
free	O
of	O
charge	O
with	O
PC	O
magazines	O
and	O
then	O
as	O
an	O
integral	O
part	O
of	O
Microsoft	B-Application
Office	I-Application
,	O
from	O
1997	O
dealt	O
a	O
significant	O
blow	O
to	O
the	O
market	O
share	O
of	O
Pegasus	B-Application
Mail	I-Application
for	O
Windows	O
and	O
other	O
email	B-Protocol
clients	I-Protocol
,	O
from	O
which	O
many	O
never	O
fully	O
recovered	O
.	O
</s>
<s>
Also	O
,	O
with	O
the	O
widespread	O
distribution	O
of	O
Microsoft	B-Application
Outlook	I-Application
,	O
user	O
expectations	O
of	O
the	O
range	O
of	O
features	O
a	O
program	O
incorporating	O
an	O
email	B-Protocol
client	I-Protocol
should	O
offer	O
(	O
Outlook	O
's	O
email	O
,	O
newsgroups	O
,	O
calendar	O
,	O
etc.	O
,	O
eventually	O
as	O
part	O
of	O
an	O
integrated	O
suite	O
)	O
did	O
not	O
fulfil	O
new	O
users	O
 '	O
expectations	O
,	O
regardless	O
of	O
the	O
features	O
of	O
the	O
email	B-Protocol
client	I-Protocol
proper	O
.	O
</s>
<s>
Trends	O
in	O
interface	O
design	O
also	O
changed	O
over	O
the	O
years	O
,	O
and	O
Pegasus	B-Application
Mail	I-Application
did	O
not	O
follow	O
those	O
changes	O
,	O
still	O
having	O
essentially	O
the	O
same	O
user	O
interface	O
it	O
had	O
in	O
its	O
first	O
Windows	O
version	O
,	O
with	O
very	O
few	O
later	O
additions	O
(	O
such	O
as	O
the	O
"	O
preview	O
window	O
"	O
mode	O
)	O
.	O
</s>
<s>
Pegasus	O
was	O
initially	O
a	O
text-mode	O
application	O
for	O
networks	O
,	O
handling	O
both	O
internal	O
and	O
Internet	O
mail	O
,	O
often	O
operating	O
in	O
conjunction	O
with	O
the	O
Mercury	B-Application
mail	O
transport	O
.	O
</s>
<s>
Pegasus	B-Application
Mail	I-Application
for	O
stand-alone	O
machines	O
was	O
initially	O
developed	O
at	O
a	O
time	O
when	O
the	O
typical	O
email	O
user	O
had	O
to	O
be	O
somewhat	O
more	O
knowledgeable	O
of	O
the	O
way	O
computers	O
,	O
the	O
Internet	O
and	O
particularly	O
email	O
operate	O
than	O
most	O
of	O
today	O
's	O
users	O
have	O
to	O
be	O
,	O
as	O
PCs	O
and	O
the	O
Internet	O
have	O
become	O
more	O
widespread	O
,	O
reached	O
a	O
broader	O
audience	O
and	O
adapted	O
themselves	O
to	O
those	O
new	O
users	O
 '	O
needs	O
.	O
</s>
<s>
At	O
the	O
time	O
Pegasus	B-Application
Mail	I-Application
was	O
first	O
conceived	O
,	O
its	O
extensive	O
array	O
of	O
features	O
coupled	O
with	O
a	O
simple	O
user	O
interface	O
provided	O
an	O
ideal	O
mix	O
for	O
most	O
users	O
 '	O
needs	O
.	O
</s>
<s>
Pegasus	B-Application
Mail	I-Application
's	O
takes	O
an	O
"	O
old-fashioned	O
"	O
approach	O
with	O
advantages	O
for	O
knowledgeable	O
users	O
with	O
complex	O
email	O
usage	O
patterns	O
,	O
or	O
who	O
need	O
special	O
features	O
.	O
</s>
<s>
support	O
for	O
three	O
encoding	O
standards	O
(	O
MIME	B-Protocol
,	O
uuencoding	B-Device
and	O
BinHex	O
)	O
;	O
</s>
<s>
a	O
powerful	O
filtering	O
system	O
,	O
so	O
much	O
so	O
that	O
it	O
is	O
possible	O
to	O
run	O
a	O
fully	O
automated	O
client-based	O
electronic	O
mailing	O
list	O
(	O
including	O
processing	O
subscribe	O
and	O
unsubscribe	O
requests	O
and	O
forwards	O
to	O
moderation	O
)	O
using	O
solely	O
Pegasus	B-Application
Mail	I-Application
;	O
</s>
<s>
the	O
ability	O
to	O
delete	O
attachments	O
without	O
deleting	O
the	O
message	O
's	O
text	O
body	O
,	O
or	O
to	O
delete	O
the	O
HTML	B-Language
version	O
of	O
a	O
message	O
while	O
keeping	O
the	O
plain-text	O
version	O
,	O
or	O
vice	O
versa	O
,	O
saving	O
disk	O
space	O
;	O
</s>
<s>
The	O
development	O
of	O
versions	O
for	O
DOS	B-Device
(	O
MS-DOS	B-Application
and	O
PC	B-Operating_System
DOS	I-Operating_System
5.0	O
and	O
higher	O
)	O
,	O
Apple	B-Device
Macintosh	I-Device
and	O
16-bit	B-Library
Windows	I-Library
(	O
Windows	B-Application
3.1	I-Application
and	O
higher	O
)	O
stopped	O
in	O
or	O
before	O
2000	O
.	O
</s>
<s>
The	O
latest	O
released	O
versions	O
for	O
DOS	B-Device
(	O
3.50	O
,	O
released	O
in	O
or	O
around	O
June	O
1999	O
)	O
and	O
16-bit	B-Library
Windows	I-Library
(	O
3.12b	O
,	O
released	O
on	O
24	O
November	O
1999	O
)	O
are	O
available	O
for	O
download	O
.	O
</s>
<s>
(	O
Version	O
3.12c	O
for	O
16-bit	B-Library
Windows	I-Library
was	O
in	O
beta-testing	O
during	O
2000	O
but	O
has	O
not	O
been	O
released	O
.	O
)	O
</s>
<s>
The	O
Mac	B-Device
version	O
(	O
2.21	O
from	O
1997	O
)	O
can	O
be	O
found	O
on	O
some	O
ftp	O
servers	O
that	O
in	O
the	O
past	O
offered	O
an	O
official	O
Pegasus	O
mirror	O
service	O
.	O
</s>
<s>
Until	O
2006	O
all	O
versions	O
of	O
Pegasus	B-Application
Mail	I-Application
were	O
supplied	O
free	O
of	O
charge	O
,	O
and	O
printed	O
user	O
manuals	O
were	O
available	O
for	O
purchase	O
.	O
</s>
<s>
In	O
January	O
2007	O
it	O
was	O
announced	O
that	O
distribution	O
and	O
development	O
of	O
Pegasus	B-Application
Mail	I-Application
had	O
ceased	O
due	O
to	O
inadequate	O
financial	O
support	O
from	O
the	O
sale	O
of	O
the	O
manuals	O
.	O
</s>
<s>
However	O
,	O
Pegasus	B-Application
Mail	I-Application
would	O
change	O
from	O
freeware	B-License
to	O
donationware	B-License
and	O
Mercury	B-Application
would	O
change	O
to	O
a	O
licence	O
for	O
fee	O
for	O
configurations	O
with	O
more	O
than	O
a	O
certain	O
number	O
of	O
email	O
boxes	O
.	O
</s>
<s>
The	O
new	O
version	O
has	O
not	O
only	O
been	O
developed	O
further	O
beyond	O
earlier	O
versions	O
,	O
but	O
has	O
been	O
ported	O
from	O
now	O
obsolete	O
v5.02	O
of	O
Borland	B-Application
C++	I-Application
to	O
Microsoft	B-Application
Visual	I-Application
Studio	I-Application
2008	O
,	O
a	O
major	O
undertaking	O
in	O
itself	O
.	O
</s>
<s>
On	O
19	O
June	O
2009	O
Harris	O
announced	O
on	O
the	O
Pegasus	B-Application
Mail	I-Application
site	O
that	O
all	O
development	O
of	O
Pegasus	B-Application
Mail	I-Application
and	O
the	O
associated	O
Mercury	B-Application
program	O
could	O
only	O
continue	O
if	O
sufficient	O
users	O
would	O
commit	O
to	O
donating	O
US$50	O
annually	O
;	O
on	O
21	O
July	O
2009	O
he	O
said	O
that	O
there	O
had	O
been	O
a	O
good	O
start	O
.	O
</s>
<s>
On	O
3	O
July	O
2009	O
Pegasus	B-Application
Mail	I-Application
4.51	O
and	O
Mercury/32	O
v4.72	O
were	O
released	O
.	O
</s>
<s>
On	O
23	O
January	O
2010	O
Pegasus	B-Application
Mail	I-Application
4.52	O
was	O
released	O
,	O
which	O
included	O
improvements	O
for	O
Windows	O
7	O
.	O
</s>
<s>
on	O
the	O
newest	O
release	O
of	O
Pegasus	B-Application
Mail	I-Application
,	O
PMail	B-Application
Version	O
5.0	O
:	O
</s>
<s>
On	O
23	O
February	O
2011	O
Pegasus	B-Application
Mail	I-Application
4.61	O
was	O
released	O
.	O
</s>
<s>
It	O
includes	O
a	O
new	O
HTML	B-Language
renderer	O
which	O
uses	O
the	O
built-in	O
Windows	O
renderer	O
of	O
Internet	B-Application
Explorer	I-Application
,	O
but	O
the	O
BearHTML	O
renderer	O
has	O
also	O
been	O
improved	O
and	O
can	O
be	O
used	O
instead	O
.	O
</s>
<s>
This	O
version	O
includes	O
Hunspell	B-Application
for	O
spelling	O
check	O
and	O
OpenSSL	B-Language
for	O
encryption	O
besides	O
further	O
improvements	O
.	O
</s>
<s>
On	O
25	O
December	O
2019	O
Harris	O
said	O
that	O
,	O
while	O
there	O
has	O
been	O
a	O
delay	O
due	O
to	O
health	O
issues	O
,	O
he	O
"	O
can	O
only	O
promise	O
you	O
that	O
there	O
is	O
progress	O
,	O
and	O
that	O
[	O
he	O
is ]	O
totally	O
committed	O
to	O
getting	O
these	O
new	O
versions	O
released	O
"	O
and	O
he	O
is	O
working	O
,	O
among	O
others	O
,	O
on	O
support	O
for	O
OAuth2	O
and	O
OpenSSL	B-Language
v	O
1.1.1	O
.	O
</s>
<s>
Some	O
are	O
:	O
OpenSSL	B-Language
was	O
updated	O
to	O
version	O
1.1.1k	O
,	O
new	O
support	O
for	O
120dpi	O
screens	O
and	O
an	O
optimization	O
for	O
the	O
HTML	B-Language
editor	O
for	O
better	O
rendering	O
.	O
</s>
<s>
Since	O
February	O
2009	O
Pegasus	B-Application
Mail	I-Application
has	O
had	O
its	O
own	O
Wiki	O
,	O
used	O
as	O
an	O
on-line	O
knowledge	O
resource	O
.	O
</s>
<s>
There	O
is	O
no	O
Linux	O
version	O
of	O
Pegasus	B-Application
Mail	I-Application
.	O
</s>
<s>
Pegasus	O
runs	O
under	O
Linux	O
using	O
the	O
Wine	B-Application
compatibility	I-Application
layer	I-Application
.	O
</s>
