SnapGene can exhibit slow start up behavior or crash unexpectedly if the SnapGene Preferences become corrupted. This may happen if you switch between running new and old versions of SnapGene.
Delete the SnapGene Preferences
To fix the issue, click to expand the appropriate section below and follow the instructions to delete your SnapGene Preferences file.
On macOS do the following:

Quit SnapGene.
Run the Terminal Application.
Copy and paste the following command into the Terminal application and hit return.
open ~/.config/GSLBiotech
This will open a hidden GSLBiotech folder in the Finder.

Move the SnapGene.ini
file, and any other files starting SnapGene.ini.*
, to the Bin.
On Windows do the following:

Quit SnapGene.
Copy the following text.
%appdata%\GSLBiotech
Click on Windows Search, paste (CTRL-v) and hit return. This will open the hidden AppData\Roaming\GSLBiotech folder
.

Select and delete the enclosed SnapGene.ini
file.
On Linux do the following:

Quit SnapGene.
Run the Terminal program.
Run the following commands to locate and delete SnapGene preferences.
cd ~/.snapgene
rm settings.ini
Run SnapGene
Once you have deleted the SnapGene Preferences file, run SnapGene, a new Preferences file will be created.
SnapGene will start as if run for the first time. Enter the requested information to start using SnapGene.