Reasons for configuration download failures will vary. Hover over the error message and it will show a reason for the failure.
When completing device templates make sure the syntax and text is permitted by the target operating system.
For example, EXOS restricts the characters allowed for the SysLocation and if the user fills out the SNMP Location in the template with illegal characters then the download will fail.
Tested the string on the CLI to confirm the validity of the string. In below case the apostrophe is not a valid character.
* EXOS-VM.12 # configure snmp syslocation “myhouse’s”
ERROR : Invalid characters are used in sysLocation.
Allowed characters: A-Z, a-z, 0-9, +-@_.,:;()/[]