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A common cause of this kind of problem is that you do not have the permission to create a new database on the SQL Server instance. If an IT administrator has installed SQL Server / Express on your computer but not added your user account (in SQL Server Management Studio) with Write/Create privileges then you will not have permission to create new databases. If you are not even listed as a user with read privileges you will be able to connect to SQL Server instance at all.

Solution 1: Request from your IT administrator to get "Create" privileges on the SQL Server instance you have problems with. Solution 2: If solution 1 is not possible you can run a light, file-based SQL Server version called LocalDB. If SQL Server 2012 / Express is installed and is running on your computer, LocalDB is already installed. Just enter "(LocalDB)\v11.0" as the name of the database server. By default, the database files will be placed directly under your profile (C:\Users\YourUserName). From Heureka version 2.3 you will also have the option to select "LocalDB" from the list of database servers, and also to install LocalDB if you have no SQL Server/Express (2012 or later) installed. LocalDB has the same database size limitations as SQL Server Express (10 GB per database).

A currently unresolved issue is the error "Access to the path 'C:\Program Files\Heureka SLU 64\DotSpatialPlugins\DotSpatialPlugins.zip' is denied", when you click on the map window in PlanWise or RegWise. It only occurs if you have used the MSI-installer for installing Heureka.

Resolution: Close the program, and the start it again as administrator. To do this, right-click PlanWise.exe from your file browser. You find the file in folder C:\Program Files\Heureka SLU 64 (or similar). Right-click on it and select Run as administrator. Next time you can start PlanWise (and RegWise) as usual, from the Start-menu.

Heureka’s growth functions are based on data for whole Sweden, for all forest types. Growth is a highly stochastic process and of course growth predictions will be uncertain. Still, for a specific even-aged stand you can expect that the predicted growth will be within 15 % of the actual outcome in 70 % of the cases independent of time horizon (Fahlvik et. al 2014), given there are no catastrophic events such as fire or storm. For larger forest areas, the total prediction error is significantly smaller.

The functions have also been tested on plots subject to uneven-aged management and for a specific stand you can expect that the predicted growth will be within 25 % of the actual outcome in 70 % of the cases. Uneven-aged management, as simulated in Heureka, relies on natural ingrowth of new trees instead of artifical regeneration. However, the number of ingrown trees varies considerably between stands and is difficult to project. The height growth for ingrown trees after selection felling is underestimated. The standing stock that consists of ingrown trees will increase with time and thus the projected forest state will be more and more uncertain.

In short, the uncertainties are largest in modelling of mortality, natural ingrowth of new trees, and establishment of young stands.

If there is a problem when starting StandWise due to SlimDX, try to solve it by installing SlimDX manually and then restart StandWise. You should download the 64-bit version for .NET 4.0.