.. meta::
    :description lang=en:
		xlSlim has extensive support for logging so issues can be investigated and solved. This page also describes other common issues.

Troubleshooting
===============

.. _logging: https://docs.python.org/3/library/logging.html
.. _Nlog: https://nlog-project.org/
.. _xlslim-support: https://groups.google.com/g/xlslim-support

Logs
----

The log files will usually contain details of what has gone wrong.

The function :func:`LogLocation` can be used to find the log location. 

Two log files are present:
 * xlslim-addin.log - this log contains xlSlim's internal logs, details of module registrations and so on.
 * xlslim-python.log - this is a regular Python log file, if your code logs with the regular Python `logging`_ module then your log messages will be redirected here.

The xlSlim internal log uses the `Nlog`_ project, the usual NLog.config configuration file can be used to amend the logging.

The Python logging can be customised by editing the PyLogging-EXCEL.conf configuration file.

Licensing
---------

For licensing issues, see :doc:`/user/licensing`, in particular note the standalone "xlSlim License Manager" application that can be used to view license details and perform offline activations.

If you are behind a firewall please whitelist api.licensespring.com on port 443.

Function Name Collisions
------------------------

If you find that the xlSlim built-in function names, as listed in :doc:`/reference/api`, clash with the names of other add-in functions then you can prefix the xlSlim function names. Edit the "PrefixBuiltInFunctions" entry in the "appSettings" section of the "xlSlim64.xll.config" file in your installation folder. The function :func:`LogLocation` will show your installation location (unless you have redirected your logs).

Adding `x_` in the config file:

.. image:: ../_static/prefix_functions_in_config_file.png
  :width: 400
  :alt: Prefix function names in config file

Results in all the built-in functions being prefixed with `x_`:

.. image:: ../_static/prefix_functions_in_excel.png
  :width: 400
  :alt: Result of prefixed function names in Excel

Functions Overwriting
---------------------

Function names are not case sensitive in Excel, so if you register a `counter()` function and later register a `Counter()` function the second function will replace the first in Excel.

VBA Replacement Code Crashing
-----------------------------

Be careful to never modify the cell currently being evaluated. Usually it is safest to use a button to run code that modifies workbooks and worksheets.

General
-------

Python environment problems can be investigated with the :func:`PythonDetails` function.

If your Excel workbook is not saved you may experience issues with object cache handle name collisions. This is due to how xlSlim constructs the cache handle using a combination of workbook name, tab name and cell adress. Unsaved workbooks share names such as Book1, Book2 and so on. Usually these problems can be solved by using the :func:`ClearCaches` to clear the caching and then saving the workbook you are working on.

Over time, the Google group `xlslim-support`_ will become a repository of common issues and solutions.