idbasp65 err = -2147467259 [Microsoft][ODBC SQL Server Driver][DBMSLPCN]SQL Server does not exist or access denied.
Goto Task Manager, click the Services tab and start MSSQL$SQLExpress11 or the SQL server services especially for the most recent database bot SQL and MSQL
if that doesn't work try the following
If this occurs after a recovery or Upgrade then Something on the server may have changed
try the following: link
Steps to restore SQL after crash
1. Install 2016 from download - SQLServer2016-SSEI-Expr (2).exe
2. Select Basic
3. There will be a new sqlserverexpressnn - 03 current next will be 04
4. Open the new instance in the SMSS (studio)
5. Copy mdf and ldf to new directory
6. Attach files