Forever unable to access subscriptions.dat (podcasts)

[savingtheworld]

Having finally populated my MB podcast shows list (more than 1000 shows), I closed MB and was going to open it and backup everything.

Instead, I got the message that

Podcast updates are locked until the next MB restart - unable to access subscriptions.dat

This subscriptions.dat is 70MB large, and takes more than 12 hours for MB to import (that's another annoying thing I can't quite figure out, but that's another matter).

Is there any way of recovering my subscriptions? I literally have a subscriptions.dat from another run hanging around, pasted it into the folder of the library of interest, and nothing is happening.

If I tried to ask for updates to subscriptions this error mesage comes up

Code

MusicBee v3.4.7764.37422P  (Win10.0), 6 May 2021 23:30:

System.NullReferenceException: Object reference not set to an instance of an object.
   at #=z1v6HwQ___W9fot3mUPBSD6cwyKsC.#=zxiGRFaFOGvGcFIrbyw==.#=zHBgv5FU=()
   at #=z1v6HwQ___W9fot3mUPBSD6cwyKsC.#=zxiGRFaFOGvGcFIrbyw==.#=zLxF5cBkoJO1V(IList`1 #=zO609_$Q=, TagCode #=zcqqWz3k=)
   at #=z1v6HwQ___W9fot3mUPBSD6cwyKsC.#=zLxF5cBkoJO1V(IList`1 #=zO609_$Q=, TagCode #=zcqqWz3k=, Boolean #=zLj9cBNQb1vDc)
   at #=z1v6HwQ___W9fot3mUPBSD6cwyKsC.#=zad6rLdU=(ApplicationCommand #=zXlo3vTk=, Object #=z46QPSpU=, #=zq6NWNemGKQIaa6EjwRusDx8= #=zO609_$Q=)
   at #=zSl3nx0ysuCOud6pBLQbkG83fN5Ji.#=z8HTLpNI=.#=zOKD_7mM=(ApplicationCommand #=zXlo3vTk=, Object #=z46QPSpU=, IList`1 #=zO609_$Q=)
   at #=z91BnV_J$yVShjfWflQwofAw=.OnClick(EventArgs #=zp6b9u0U=)
   at System.Windows.Forms.ToolStripItem.HandleClick(EventArgs e)
   at System.Windows.Forms.ToolStripItem.HandleMouseUp(MouseEventArgs e)
   at System.Windows.Forms.ToolStripItem.FireEventInteractive(EventArgs e, ToolStripItemEventType met)
   at System.Windows.Forms.ToolStripItem.FireEvent(EventArgs e, ToolStripItemEventType met)
   at System.Windows.Forms.ToolStrip.OnMouseUp(MouseEventArgs mea)
   at System.Windows.Forms.ToolStripDropDown.OnMouseUp(MouseEventArgs mea)
   at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
   at System.Windows.Forms.ToolStrip.WndProc(Message& m)
   at System.Windows.Forms.ToolStripDropDown.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

[Steven]

It means the subscriptions.dat file is not accessible

In MusicBeeLibrarySettings.ini (located in the root music folder)
look for "OrganisationPodcastsFolderPath"
if its not there MB will look in the Podcasts sub-folder of the root music folder. Otherwise correct the path to the actual folder the subscriptions.dat file is located