If you somehow lost your admin right on your dev SQL Server, here’s how you can add the logged in user account again.
You will have to start SQL Server in single user mode and than add the local account in the sysadmin role.
Start SQL Single user:
SQLServr.Exe –m
Add your account:
SQLCMD
1> SP_ADDSRVROLEMEMBER ‘’,’SYSADMIN’
2>go