While working with SharePoint 2013 list, saving the data I got an error saying that “The server was unable to save at this time. Please try again.” As shown the image below.
By checking the logs I have found following error “Memory gates checking failed because the free memory is less than 5% of total memory. As a result, the service will not be available for incoming requests. To resolve this, either reduce the load on the machine or adjust the value of minFreeMemoryPercentageToActivateService on the serviceHostingEnvironment config element.
After verifying the details in event logs, Services and Task Manager Details, I have found that error causing low memory. To fix this error we have to restart “SharePoint Search Host Control” and “SharePoint Administration service”. By refreshing this error we can have a lot of memory will be freed. We have same error when custom application deployed without disposing object. In that case we need to reset the IIS. By resetting the IIS We can save the list data without error.
Hope this helps.