Reporting Problems or Possible Bugs

If you find what seems to be a problem or a possible bug with GEMPACK, please report it as indicated below.

We are usually able to respond to such reports within 48 hours. If a bug is found, we are usually able to send a bug fix within that time.

Save Files Before Trying to Work Around the Problem

If you find a possible bug, we know that you will want to try to work around it.

But please, first save the files as they are. Otherwise we know from experience that you may find it impossible to reproduce the problem.

If we can reproduce a bug, we can usually fix it quickly. But if we cannot reproduce it, we probably cannot help.

Making a ZIP of the files needed to reproduce the problem

Please make a single ZIP file containing all files needed to reproduce the problem. We describe some different cases, GEMSIM and Tablo-generated programs, RunDynam, and Windows programs, and the files involved.

GEMSIM and TABLO-generated programs

If the problem occurs when running GEMSIM or a TABLO-generated program we need

  1. the TAB file (extension *.tab),
  2. the stored-input file, if used, to run TABLO (often but not always has extension *.sti),
  3. the Command file (extension *.cmf),
  4. all starting data files, including supplementary data files, if any (extension usually *.har but might be text *.txt or similar),
  5. any shock files, if used (extension usually *.har but might be text *.txt or similar), and
  6. the log file which shows the problem (if possible). The log file helps us ensure that we have reproduced the reported problem.

Check That You Have Included All Files. We strongly recommend doing this check. Unzip your ZIP file into an empty directory. Then run the job(s) again to check that you can reproduce the problem. [If the problem is with a simulation, make sure that you start by running TABLO.] If you do not reproduce the problem your job probably stopped because of a missing a file. Add the missing files to your ZIP file and try the check again. When the check works follow the advice below for sending the ZIP file to us.


Use the RunDynam menu item Zip ⯈ Save Ingredients as ZIP archive to create a ZIP file.

We also need the LOG file from the relevant year/period so that we know whether or not we have reproduced your error. Please tell us which year/period and which run, Base/Rerun/Policy, the crash occurred on.

RunDynam ZIP Archives normally contain executable files and can be too large for email. An email with such a ZIP archive attached will probably not be delivered. Follow the advice below to send the ZIP file to us using a file sharing service.

Windows programs

If you have a problem with a GEMPACK Windows program such as TABmate, ViewHAR, ViewSOL, Analysge or WINGEM you should zip up and send to us any input files needed to reproduce the problem. You may need to describe the precise sequence of button-clicks which led to the problem. Sometimes a picture is useful, which you could save in a Word document as follows:

Which ViewHAR.EXE?

You may have several copies of a program, eg, ViewHAR.EXE, on your hard drive. For example, ViewHAR.EXE may be in your GEMPACK (usually C:\GP), RunGTAP, or RunDynam folders. RunGTAP and RunDynam usually use their own local copies of ViewHAR. If there is a problem, you'll need to identify which copy of ViewHAR.EXE is to blame.

Open the ViewHAR that caused the problem, and use menu command Help ⯈ About/Diagnostics. The About screen tells you the location of that ViewHAR.EXE.

Once you have identified which ViewHAR is causing the problem follow the advice below to send the ZIP file to us using a file sharing service.

When a fix is available perhaps several copies of ViewHAR.EXE, or some other program, will have to be replaced. You can use the command line to find the different ViewHAR.EXE files. Open a DOS box, and move to the C\: root by typing:

cd \

Then type:

dir/s ViewHAR.EXE

Quite often, problems with Windows programs may be resolved by downloading and installing the latest versions. You may need to install the update three times, in your GEMPACK (usually C:\GP), RunGTAP, and RunDynam folders.

Sending Files Needed to Reproduce the Problem

To report your problem please send an email to and include these 3 items

We value informative bug reports

Each year we award a virtual medal to the best bug reporter.

See also:
Frequently Asked Questions