EZNEC 4.0 FAQ
I'm having trouble installing or running the program on a new computer.
See Using Older Versions.
My program was
working, but now it fails with the message 'Runtime error 336:
Component dwsbc36.ocx or one of its dependencies not correctly
registered, a file is missing or invalid'.
Several spyware removal programs
incorrectly identify dwspy36.dll, a file used by dwsbc36.ocx, as
spyware and recommend its deletion. See "What is dwspy36.dll in the
program directory", below, for information about these files.) The message
occurs when the file is
deleted. As of v. 4.0.5, EZNEC
uses these files, so updating the program to v. 4.0.5 or later will
solve the problem.
When I try to install
EZNEC I get the message 'C:\WINDOWS\SYSTEM32\AUTOEXEC.NT. The system
file is not suitable for running MS-DOS and Microsoft Windows
applications' or other message involving AUTOEXEC.NT.
This is most often caused by the Windows XP
Pack 2 (SP2) installation deleting (for unknown reasons) the
Autoexec.nt file which is required to run 16 bit programs. The EZNEC
installation program is intentionally an older type in order to keep
download size smaller and updates simpler, and requires 16 bit
(DOS-type) operation during part of the process. (EZNEC
doesn't.) You should be able to solve the problem by locating a copy of
Autoexec.nt in your C:\Windows\Repair directory (the directory might be
C:\Winnt\Repair on systems upgraded from Windows 2000) and copying it
into your Windows system directory C:\Windows\System32 (or
C:\Winnt\System on some upgraded systems). If you need further
this doesn't fix the problem, please let me
Will EZNEC 4.0 run
under Windows XP? Vista? Windows 7?
to all. EZNEC
pro v. 4.0
users will need to download and install the latest update for Vista
or Windows 7 operation, but no action is required for other users. For information
about running EZNEC under 64 bit versions of these systems, see the
Will EZNEC 4.0 run
under 64 bit operating systems?
and earlier won't install on 64 bit systems, and installing the latest
update won't correct the problem. If your original EZNEC v. 4.0
program is earlier than v. 4.0.30 and you've upgraded to a 64 bit
operating system, contact
instructions for obtaining a new installer. You can determine your
version number by right-clicking EZW.exe or EZWpro.exe in Windows
Explorer, choosing Properties, then clicking the Version tab.There is no problem running EZNEC v. 4.0
a 64 bit computer, as long as the operating system is 32 bit. Except for
identified as 64 bit, Windows XP and Vista are 32 bit systems.
Will EZNEC 4.0 run
under Windows 95?
I'm sorry, no. Following
current trends, the compiler used for creating the calculating engines
won't produce Windows 95-compatible code, and at least one of the
third-party components used for advanced functionality won't operate
under Windows 95.
EZNEC hangs whenever
I try to open a top level menu, or at other times.
This problem occurs with EZNEC
and earlier on systems having a video adapter with an NVidia chip set,
but it has been fixed in v. 4.0.17 and later programs. If you
have this problem or have implemented the workaround of setting the
program to run in 256 color mode, update your program by downloading
and installing the latest update release. EZNEC
users should go to http://eznec.com/ez40updates/.
users should go to the URL printed on the distribution CD. If you're
using the demo program, download and install the latest demo from http://eznec.com/demoinfo.htm.
generally be necessary to start any non-pro program once after
installing the update, then shutting it down, before it will run
properly with an NVidia adapter without being in 256 color mode. Please
let me know if
you see this problem
with any v. 4.0.17 or later EZNEC
Does EZNEC 4.0 use NEC-4 for calculations?
Of the five EZNEC
program types (demo, standard EZNEC,
uses NEC-4. NEC-2 is the calculating engine used by the other EZNEC
See the next item, below, for more information.
Can EZNEC 4.0 use the
antenna description files I created with an earlier version?
can even read and translate DOS EZNEC
ELNEC (.EN) files -- just include the
extension (.EN) when specifying the name of an ELNEC file to open.
versions of EZNEC can also read
and use files written by
EZNEC 4.0. EZNEC
4.0 uses the same plot
file format as EZNEC
v. 2.0 and 3.0, and can display plots saved by ELNEC or any version of EZNEC.
If I buy the CD-ROM
version, does the CD-ROM have to be in place when running the program?
No. All necessary files are
installed on your hard drive. The CD-ROM is needed only for
installation. If desired, the CD-ROM files can be copied to a hard
drive or Zip drive and the program installed or re-installed from there.
Where's the manual?
The manual is an
integral part of the program. With EZNEC
4.0 running, In the EZNEC 4.0
main window), click Help on the menu bar, then choose Contents to view
the manual. You can also open the manual to the relevant topic from
places in the program by pressing F1.
Is it possible to get
a printed manual?
Yes, if you're willing to print
it yourself. If you
on a CD-ROM, you'll find it in the
Printable Manual directory on the CD-ROM. Otherwise, you can download
it. Clicking here
you to the page where you can get more information. No pre-printed
What are the EZNEC and EZNEC+ v. 4.0
The limit for EZNEC 4.0
is the same as for earlier versions, 500 segments maximum. This allows
approximately 25 wavelengths of wire, or 50 beam elements. EZNEC+ 4.0
allows 1,500 segments, and the
professional EZNEC 4.0 programs
accommodate up to 20,000
Will EZNEC 4.0
overwrite previous versions?
v. 4.0 will overwrite and update EZNEC v. 3.0
if installed in the same directory. It will not affect earlier (DOS)
Will installing or
uninstalling EZNEC erase or overwrite my existing description or trace
What's the difference
between the upgrade version and full program?
There are no different
"upgrade" and "full" or "new"
versions. There's only one version, and it's a complete, independent
program which doesn't require any other program or older version in
order to install or function.
The only difference between a new purchase and an upgrade purchase is
the price; the program is the same.
Is there any difference between the download and CD-ROM products?
The installed program
is exactly the same -- the
only difference is in the format of the files used for installation.
The download product is a single executable file, for convenient
downloading. It expands and creates temporary files during the
installation process, which are deleted when the installation is
complete. The CD-ROM contains several files. Once
installed, the programs and disk space requirements are identical. You
may need to re-install EZNEC
in the event of a hard drive failure or
change to your computer system, so you should always keep either the
CD-ROM or downloaded file. If you don't have any way to back up the
downloaded file on some medium other than your primary hard drive, you
should order the CD-ROM (with or without the download) to protect
against loss of the program in the event of a hard drive failure.
My EZNEC v. 4.0 runs
extremely slowly. Why?
Some versions of McAfee Antivirus sofware, when running
in the background detection mode, can cause extremely slow operation of
EZNEC v. 4.0 calculations. This
problem can suddenly appear
antivirus software is updated. Apparently, the antivirus software
intercepts and analyzes the communications between the calculating
engine and the main program. These communications are numerous and
frequent, so the rather slow analysis process by the antivirus program
greatly slows EZNEC
operation. The only certain solution is to disable
the background checking feature of the McAfee software while running EZNEC v. 4.0. So far, this
has been reported only with McAfee version 4, and it appears that
version 6 and later versions might not have this effect on EZNEC.
however. Other virus-detecting software could possibly have a similar
effect, so if you encounter exceptionally slow operation, try disabling
any anti-virus software you have running, and let me know if it
solves the problem.
What is dwspy36.dll
in the EZNEC program directory?
Some people have expressed
concern about dwspy36.dll
and wonder what its function is. This file is a "subclassing" control,
part of a third-party utility package called SpyWorks, purchased from
Desaware, a highly respected company which is well known to the Visual
Basic programming community. This package allows functionality beyond
that provided by Visual Basic or normal Windows programming but despite
its rather sinister name is not "spy" software. When you attempt to
reduce the size of graphical windows below a certain point, EZNEC
the minimum size. This size limiting isn't possible with Visual Basic
(except with "bounce-back" type operation), so a technique called
"subclassing" is used. EZNEC
the normal Windows message sent
when a window is resized and directs it to code that limits the window
size. The SpyWorks control (dwsbc36.ocx, which uses dwspy36.dll) allows
this functionality. (It's
apparently so named
because of its ability to "spy on" -- intercept -- messages
sent to and from the Windows operating system by applications during
normal operation.) Some versions of EZNEC
dwsbc36.ocx and dwspy36.dll in the EZNEC
directory; other versions installed them in the Windows system
directory instead. An increasing number of spyware removal programs
misidentify dwspy36.dll as spyware and delete it, which caused EZNEC
Because of this problem, EZNEC
was modified at version 4.0.5 to use a recompiled version of a similar
DesaWare product, rather than dwsbc36.ocx and dwspy36.dll. V. 4.0.9 and
later use an entirely different and newly compiled control. If you have
program type of version 4.0.5 or later, you can safely delete
dwsbc36.ocx and dwspy36.dll from the EZNEC program directory if they're
there. I don't, however, recommend deleting them from the Windows
system directory because some other legitimate application might be
No version of
does keystroke logging or any other type of user activity
recording, reporting, or Internet connection. For more information
about the SpyWorks package, see
http://www.desaware.com/SpyWorksL2.htm, and for more information about
subclassing, see http://www.desaware.com/Subclassing.htm.
>What language is
EZNEC 4.0 written in?
The interface portion of the
program was written in
Microsoft Visual Basic 6.0. It consists of more than 50,000 lines of
code, not counting comments. I wrote every line, and it took about two
years of essentially full time work to develop the first Windows
calculating engine is a modified version of the public domain NEC-2
program. It's written in Fortran, and incorporated as a separate
Where can I get more EZNEC models?
The CD included with the 20th and later
editions of the
ARRL Antenna Book
models of a wide variety of antennas. While specially created to work
with the EZNEC ARRL
program which also comes with the Antenna
Book, they're also standard EZNEC
which work normally with EZNEC 4.0
without the EZNEC
files, the ARRL Antenna
is a bargain, but the files make it even more so. Also, check http://www.cebik.com
for models and
other good information.