error code 61

i took the advice of people online and created a sparse image file as a way of password protecting folders on my hard drive. worked well for a while. these days, when i try to add or delete files from that sparse image, i get error 61 code. why can't i write/delete from that mounted image anymore?

 

the image is on an external hard drive, used for backups. i don't think i've ever messed with any of the permissions. when i created it, i gave it a password. i can still enter the password, which unlocks and mounts the image. from there i can open files and such, so i have read access. i just can't add to or delete from the image. somehow i lost those permissions. i attached a shot of the "get info" screen on the drive. i notice on the bottom now it says "you can only read" even though the option below it says "read/write". those buttons are grayed out and cant be clicked.

i ran disk utility before and hit both verify disk and repair disk, both said to have went through without error.

 

oh i figured it out. apparantly the image was locked. i noticed this when i did "get info" on the image itself before mounting it. unlocked and works fine now =)