Merge pull request #697 from Icinga:doc/ikwb_scom_uninstall

Docs: Adds IWKB entry `IWKB000017` handling issues with failed checks once SCOM is uninstalled

Adds IWKB entry `IWKB000017` handling issues with failed checks once SCOM is uninstalled as example

Author: LordHepipud

doc/100-General/10-Changelog.md

@@ -23,6 +23,7 @@ Released closed milestones can be found on [GitHub](https://github.com/Icinga/ic
 
 ### Enhancements
 
+* [#313](https://github.com/Icinga/icinga-powershell-framework/issues/313) Adds IWKB entry `IWKB000017` handling issues with failed checks once SCOM is uninstalled as example
 * [#587](https://github.com/Icinga/icinga-powershell-framework/issues/587) Adds support to create own snapshot repositories with `New-IcingaRepository`
 * [#631](https://github.com/Icinga/icinga-powershell-framework/pull/631) Deduplicates `-C try { Use-Icinga ...` boilerplate by adding it to the `PowerShell Base` template and removing it from every single command
 * [#669](https://github.com/Icinga/icinga-powershell-framework/pull/669) Adds new metric to the CPU provider, allowing for distinguishing between the average total load as well as the sum of it

doc/300-Knowledge-Base.md

@@ -24,3 +24,4 @@ For this reason you will find a list of Icinga knowledge base entries below. Ent
 | [IWKB000014](knowledgebase/IWKB000014.md) | Installing or Updating Icinga for Windows causes error messages regarding `framework_cache.psm1` errors |
 | [IWKB000015](knowledgebase/IWKB000015.md) | Got JSON, but not an object, from IfW API on host 'localhost' port '5668': "Exception while calling \\"Fill\\" with 1 arguments: \\"Invalid syntax near \\"`<Argument>:`\\".\\"" |
 | [IWKB000016](knowledgebase/IWKB000016.md) | Checks using Performance Counter fail with various messages like `Exception of type 'System.OutOfMemoryException' was thrown` or `Icinga Invalid Configuration Error was thrown: PerfCounterCategoryMissing: Category "Memory" not found` |
+| [IWKB000017](knowledgebase/IWKB000017.md) | Icinga throws exception during plugin execution after uninstalling SCOM or other vendor software using PowerShell modules |

doc/knowledgebase/IWKB000017.md

@@ -0,0 +1,25 @@
+# Icinga Knowledge Base - IWKB000017
+
+## Short Message
+
+Icinga throws exception during plugin execution after uninstalling SCOM or other vendor software using PowerShell modules
+
+## Example Exception
+
+Icinga throws the exception
+
+`The Icinga PowerShell Framework is either not installed on the system or not configured properly. Please check https://icinga.com/docs/windows for further details`
+
+once a plugin is executed from the Icinga Agent after SCOM is uninstalled as example.
+
+## Reason
+
+In some cases uninstalling certain software components which also ship PowerShell modules, like the Microsoft SCOM, Icinga for Windows will stop working. The Icinga Agent will assume that the PowerShell Framework is no longer installed as it cannot find the module afterwards.
+
+## Solution
+
+The simple solution is to restart the Icinga Agent service which will resolve this issue and reload the environment variables. Afterwards the checks will work as before.
+
+```powershell
+Restart-Icinga
+````