The following segments will assist and redirect you about the common technical Faq's :

Error while performing indexing using DataImportHandler

Setup core if your Solr is hosted on shared server

How can I connect to Solr ?

TimeOut Expiration Error on Plugin installation

Category and Manufacturer Navigation not working

How Can I search with synonyms ?

Facet Filter with % does not work

Licensing Issues

Responsive filter not working with noptemplate theme

Font error in Google Chrome 'Refused to load the font '<URL>'

Implement WebRequest for StartIndexing method