iphone 4 - barcode scanning apps

[lullu]

I have the red laser app on my phone for scanning barcodes and it no longer works. I added 3 other scanning apps and they don't work either. Does anyone have a solution? I turned the phone off for a while but that didn't fix the problem.

 

[TEG]

I Use the at&t scanner app, and it works great. Did you see if perhaps your lens is dirty, or do the apps just fail to function?

TEG