Or similar: Your query is malformed. Please rephrase your query
Only observed in 2010
When performing a search the error message “Your query is malformed. Please rephrase your query.” may appear instead of search results in certain conditions:
1. Wrong search syntax was used in the query. For example, when using logical operators, they need to be placed correctly between keywords.
The solution, in this case, is to examine the query made (check the search fields or search URL) and correct the query accordingly.
2. A limitation exists for the naming of Ontolica Search searchable properties, as well as SharePoint managed properties. The following words should not be used to name these properties: SELECT, FROM, WHERE, ORDER BY, SET, AND, OR, NOT.
The solution, in this case, is to rename Ontolica properties, as well as SharePoint, managed properties, so that the SQL reserved keywords are not used any more.