Is your network where iDRAC is configured have access to internet and downloads.dell.com?
In iDrac 9 -> maintenance -> System update -> Manual update -> Location Type "HTTPS"-> type in HTTPS Address: downloads.dell.com I have multiple servers where I click 'Test network Connection' and I get the below error.  "LC023: Cannot access network share. Check network share access credentials (IP address, user name, password, share type, and so on). Refer to your product documentation for more details." I can get to downloads.dell.com manually on a PC which redirects me to www.dell.com/support/home/en-us.   Any help on would be appreciated.        
iDrac check for updates -- LC023: Cannot access network share