Why are some of my pictures in an unsupported file??

[AC Question]

In trying to delete old pictures directly from my phone, it looks as if the pics I took starting about a year back show unsupported file and I can not delete them from the phone......some update or something I did inadvertently must have chanted the format.
How can I get these deleted from phone before downloading to my computer. Thanks.
Techno challenged.....in Cali

 

[B. Diddy]

Welcome to Android Central! Are these photos saved to Internal Storage or a microSD card? If you connect the phone to your computer via USB and use Windows Explorer, can you open the photos?

 

[dellaraymon]

How can I delete unsupported files on my phone.