There could be several reasons - the path to the save is too long, or there are non-English characters in the path to the save. Try eliminating both. If that doesn't help, click the Copy button in the error window and paste the text here.
Android:0.6.0.2 (Aberto)
System.IO.DirectoryNotFoundException: Could not find a part of the path "/content:/com.android.externalstorage.documents/tree/primary%3ADocuments/document/primary%3ADocuments%2Fsave.mss".
at System.IO.FileStream..ctor (System.String path, System.IO.FileMode mode, System.IO.FileAccess access, System.IO.FileShare share, System.Int32 bufferSize, System.Boolean anonymous, System.IO.FileOptions options) [0x00000] in <00000000000000000000000000000000>:0
at System.IO.FileStream..ctor (System.String path, System.IO.FileMode mode, System.IO.FileAccess access, System.IO.FileShare share, System.Int32 bufferSize) [0x00000] in <00000000000000000000000000000000>:0
at System.IO.File.ReadAllBytes (System.String path) [0x00000] in <00000000000000000000000000000000>:0
at SaveUtility.LoadExternalSave (System.String filePath) [0x00000] in <00000000000000000000000000000000>:0
at UI.Saves.SavePanel.OnSuccess (System.String[] paths) [0x00000] in <00000000000000000000000000000000>:0
at SimpleFileBrowser.FileBrowser.OnSubmitButtonClicked () [0x00000] in <00000000000000000000000000000000>:0
at UnityEngine.Events.UnityEvent.Invoke () [0x00000] in <00000000000000000000000000000000>:0
at UnityEngine.EventSystems.ExecuteEvents.Execute[T] (UnityEngine.GameObject target, UnityEngine.EventSystems.BaseEventData eventData, UnityEngine.EventSystems.ExecuteEvents+EventFunction`1[T1] functor) [0x00000] in <00000000000000000000000000000000>:0
at UnityEngine.InputSystem.UI.InputSystemUIInputModule.ProcessPointerButton (UnityEngine.InputSystem.UI.PointerModel+ButtonState& button, UnityEngine.EventSystems.PointerEventData eventData) [0x00000] in <00000000000000000000000000000000>:0
at UnityEngine.InputSystem.UI.InputSystemUIInputModule.ProcessPointer (UnityEngine.InputSystem.UI.PointerModel& state) [0x00000] in <00000000000000000000000000000000>:0
at UnityEngine.InputSystem.UI.InputSystemUIInputModule.Process () [0x00000] in <00000000000000000000000000000000>:0
#0 0x74e1cfe06c (libunity.so) ? 0x0
#1 0x74e23a01c8 (libunity.so) ? 0x0
#2 0x74e19a2164 (libunity.so) ? 0x0
#3 0x74e19a2074 (libunity.so) ? 0x0
#4 0x74cc23030c (libil2cpp.so) ? 0x0
#5 0x74c83e9908 (libil2cpp.so) ? 0x0
#6 0x74c8496be4 (libil2cpp.so) ? 0x0
#7 0x74cb6433dc (libil2cpp.so) ? 0x0
#8 0x74cc2ab23c (libil2cpp.so) ? 0x0
#9 0x74c917bdac (libil2cpp.so) ? 0x0
#10 0x74cbe08610 (libil2cpp.so) ? 0x0
#11 0x74cbe07bf4 (libil2cpp.so) ? 0x0
#12 0x74cbe0d790 (libil2cpp.so) ? 0x0
#13 0x74c8347248 (libil2cpp.so) ? 0x0
#14 0x74c8347194 (libil2cpp.so) ? 0x0
#15 0x74e1c3c9ac (libunity.so) ? 0x0
#16 0x74e1c50764 (libunity.so) ? 0x0
#17 0x74e1c5c04c (libunity.so) ? 0x0
#18 0x74e1a4df9c (libunity.so) ? 0x0
#19 0x74e1b2a2ec (libunity.so) ? 0x0
#20 0x74e1b2a32c (libunity.so) ? 0x0
#21 0x74e1b2a5d0 (libunity.so) ? 0x0
#22 0x74e1ce5c68 (libunity.so) ? 0x0
#23 0x74e1ce6be8 (libunity.so) ?
0x0
#24 0x73422790 (boot.oat) ? 0x0
Oh... This is a known issue — on newer Android versions, the file picker returns a special system path that our game can't read directly. We'll fix this in the next update.
Workaround for now: Instead of picking the file through the browser, manually copy your save.mss file to the game's internal folder:
/storage/emulated/0/Android/data/com.wildpear.magicacademy/files/
Then try loading from there. If you can't see the Android/data folder, use a file manager like X-plore or Total Commander — the default one often hides it.
40 days ago(+1)
I've found the cause of this issue, but we'll only be able to implement the fix in the next version.