There are some basic reason if you not able to start the SQl Server Service:
1)
Master
db files are not found on their location or corrupted
2)
Instance
specific binaries or related binaries are either corrupted or disk is not
available.
3)
Registry
may be corrupt;
4)
Permissions
may be messed up
5)
Antivirus
may block the services to start
6)
Memory
is not sufficient on server to allocate to SQL Server that time.
You can Troubleshoot the issue using following way:
1) Check the SQL
Server error log if created in instance root directory in Log folder
2)
Application
and System logs in event viewer log
3)
Check
resource (Memory and CPU) utilization on server that time.
4)
Check if
relevant disks where SQL Server binaries located are attached/accessible from
server
