It seems it is related to path where the plugins are.
After getting the error, run these lines in Matlab, and paste the result in this post
% Get list of Plugins that are installed
InstPlugs = bst_plugin('GetInstalled');
% For the Installed Plugins that are Loaded at the Startup, print the Path of their logos
{InstPlugs(logical([InstPlugs.AutoLoad])).LogoFile}