This error is related to Microsoft SQL. In order to fix it please have a look at the following instructions:
1. Search the Services in your system.
Please note that Services should be always run in Admin mode:
2) The system will open a window where you have to find SQL Server (HS2011) service.
3) Right click on it and choose Start.
After that the system will the SQL service again and you will be able to open the system normally.