Your changes could not be saved because this SharePoint Web site has exceeded the storage quota limit. You must save your work to another location. Contact your administrator to change the quota limits for the Web site.
Sometimes you will get the above error in SharePoint. In this post we will discuss how to resolve the issue.
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Sometimes you will get the error while creating a list or document library or sometimes you will get the error while saving List as a template
This error occurs if the Web site has exceeded the storage quota limit. A quota specifies the storage limits so that it defines the maximum amount of data that can be stored in a site collection.
You can increase the quota limit from SharePoint Central Administration.
Open SharePoint Central Administration, then from the Application Management Page section go to SharePoint Site Management section and there click on Quota Templates.
Also you can change by using STSADM command. Below is the full command:
stsadm -o setproperty -propertyname max-template-document-size -propertyvalue 524288000