Why do I get an error that the sd card is write protected when I try to add a movie?

[midsm]

I tried to add a couple (one at a time) music videos to my 128gB micro card and each time I get a write protected error.
I used Any Video Converter program to convert .avi files to Samsung Tab .mp4 files
Can somebody please post the process to add movies to the card?
Thanks.

 

[FF22]

I will just throw out some questions: How large are the files? What is the formatting on the card? How are you copying them - USB cable, or card moved to computer and copying that way?

Have you been able to move other files to the card?

 

[midsm]

Yeah sorry should have given more info.
First I'll apologize, never had a tablet before so am very unfamiliar with adding moving things around. My card has been formatted (again this am) while in the tablet. When I go to settings (while it's plugged into usb) it shows total and available space as 125gb, and under "Unmount and Format SD Card" says MTP of PTP function is active, but all that is in gray toned lettering, not bright as when I don't have the usb plugged in (the text changes from bright to dull when usb plugged in). I tried to copy and paste pictures; gives message " Cannot Copy. The device has either stopped responding or been disconnected." I tried the photo file since it's smaller about 320kb. (is it copy and paste to the sd card?)
Sorry, as I said, not sure how to do this.
Thanks for any and all help.

 

[FF22]

Brand and speed of card? Where did you get the card - there are counterfeit cards that can create problems. This is my first Android device. I have a Blackberry Playbook tablet and BB phone.

I just plugged in the usb. Mine shows as yours with the GRAY-out since the device is connected to computer and you canNOT unmount of change the card stuff.

But I just copied a picture over with no problems to a 64gig Sandisk card. Used Windows Explorer. I see the CARD and TABLET. Can you copy to the Tablet (internal memory). Oh, where did you try copying? To which Folder? I copied the picture to "photos" My music in in the "music" folder where I have almost 1,110 files taking up 7gigs of space.