KMP wrote:
If the paper has a pebble texture to prevent finger prints, it will often reflect back from the scanner light and show as lots of small white specs.

That's the most likely culprit.

If it's glossy paper, you're probably seeing dust. I keep a can of air and an anti-static brush by the scanner for just that reason. I also wear cotton gloves, but that's for negatives - it may be too difficult to peel the photos off the scanner with gloves. Either way, watch for fingerprints.

Zack Zoll wrote:

That's the most likely culprit.

If it's glossy paper, you're probably seeing dust. I keep a can of air and an anti-static brush by the scanner for just that reason. I also wear cotton gloves, but that's for negatives - it may be too difficult to peel the photos off the scanner with gloves. Either way, watch for fingerprints.

I used vinyl gloves to prevent finger prints and periodically used glass cleaner. Perhaps it is dust but it's annoying how quickly it reappears. If I had a macro lens and appropriate lighting I might try that method. Hopefully  though since these white dots are so distinct one can easily enough use surrounding color to patch the digitals up.