"And that was good advice, good advice. Good advice costs nothing, and it's worth the price. I sincerely doubt That the world could do without My good advice." Alan Sherman

You currently have: openFileDialog1.Filter = "All Image Files|\*.bmp;\*.ico;\*.cur|All files (\*.\*)|\*.\*"; To add a filter for PNG files (for example) simply add the filename template between 'cur' and the '|' before 'All Files', not forgetting to separate it by a semi-colon. openFileDialog1.Filter = "All Image Files|\*.bmp;\*.ico;\*.cur**;\*.png**|All files (\*.\*)|\*.\*"; I have tried to make my additions stand out by superscripting it. Have a go with the others yourself. Henry Minute Do not read medical books! You could die of a misprint. - Mark Twain Girl: (staring) "Why do you need an icy cucumber?" “I want to report a fraud. The government is lying to us all.”

It means that you're asking a C# question on a C++ forum. It was ever thus, the Neophiles will always rush out and get 'The Latest Thing' at a high price and with all the inherent faults - Dalek Dave.

In addition to Luc's suggestion of encrypting off a file stream, have you considered compressing before encrypting? Assuming that your images are not JPG (or some other format that is already compressed) you might get a major benefit from compression.