New Items Vanish from Pictures Library

I keep my photos in the Windows 7 Pictures Library on my laptop. The library is copied to a portable hard drive.

I recently collected some new photos on the portable drive and later dragged them to the corresponding folder on the computer. All OK until the computer was rebooted, when the new photos apparently vanished from the folder. A search showed that they were still there, and they became visible when the folder was dragged to the desktop. But they vanished again when it was replaced in the library.

I deleted the whole folder from the library and replaced it with the copy on the portable drive. All was well, including the new photos. But further photos imported from the portable drive still vanish as described.

This only seems to happen with the hard drive: individual photos imported from an SD card or copied to the library from other applications are OK.

Maybe I'll just have to collect new photos in a different way, or import the whole folder each time, but I'd be grateful for advice.

Thanks, mitchell65. I'm certainly not offended, being far from expert and always grateful to learn.

Actually, I did realise that the libraries are essentially a collection of shortcuts but maybe I didn't explain the problem clearly. I open the Pictures Library then click on a folder link to display the file links (thumbnails are my choice). I then drag a new photo from an external hard drive and drop it into the display. A new thumb appears and remains in place, even if I close the library then return to it. But, after shutdown and reboot, I find that the new thumb has disappeared when I next go to the folder via the library. If I open the folder directly, eg by dragging the library link to the desktop or go via Windows Explorer, the thumb shows. When I return the link to the library, the thumb vanishes again. I've discovered that it can be restored if the folder is first opened via the navigation pane on the left of the library, but that's as close as I can get to a solution.

This does not occur if I follow the same procedure but take the new photo from, eg, an SD card or an e-mail.

Hope all that makes sense!

Thanks to all for the responses. I tried copy/paste instead of drag/drop and it was successful. I'm grateful.

mitchell65 said:

Well I am getting a bit confused here. When you say you "I then drag a new photo from an external hard drive and drop it into the display. " (Q1) What display are you dragging it to? (Q2) How do you navigate to an external hard drive without using the left hand pane? (Q3) Do you mean a separate hard drive that is not linked to the picture library? (Q4) How can you drag the "Library Link" to the desktop. I not sure what you mean there!
A couple of screen shots would be very helpful here!
I need some help now, I think

Sorry for the confusion, mitchell65. Screen shots would not be for public display, but I'll try to explain.

I go to Libraries and double-click Pictures. This opens Pictures Library with icons in folder order as I have chosen (call this Stage 1). I double-click a folder icon, then a sub-folder icon if there is one. This opens with picture icons arranged by date, again as chosen (call this Stage 2).

Q1. The display I am dragging to is Stage 2. A new picture icon appears as soon as I drop.

Q2-3. I navigate to the external drive by selecting the Windows Explorer option in the Autoplay box which appears when the drive is connected to a USB. The drive is not linked to the Picture Library. (I did not know this was possible until I read the link in your first reply. I'll consider this further tomorrow as it's nearly time for my Horlicks.)

Q4. "Library link" was my clumsy terminology for a folder icon at Stage 1.

Hope this clarifies rather than mystifies.