When trying to activate a sandboxed solution, Got below error message:
This is because of the Sandbox solution resource limit. To fix this issue, just increase the site collection Sandbox solution resource quota in site collection quotas and locks.
Go to: Central Administration >> Application Management >> Configure quotas and locks >> Pick the target site collection.
Increased the Sandbox solution resource quota under “Limit maximum usage per day to 0 points” to 100 points, Problem solved!
In another case, whey trying to deploy a sandbox solution from visual studio, it reported the same error “Error occurred in deployment step ‘Add Solution’: The site collection containing this sandboxed solution has exceeded its daily resource usage quota” and the fix is same!
The same thing applies to office 365! Set the “Resource Usage Quota” from SharePoint Online Administration Center.