When the program deletes from the data file, it marks the individual items as deleted, but the data physically stays in the file. It is removed during file compression. Therefore, if you delete some items and need to recover them later, and the Undo function can not be used (the file was meanwhile closed, indexed, etc.), you can use this function. The items are always recovered in a new file which is automatically created (non-consistent, duplicate data is usually created during recovery as a measured point without the station header, etc.). From this data, the needed data can be copied to any other file.