Girls act afraid of me

Hi, I joined this forum simply because I did not know what else to do. I really would like a female perspective.

I have a problem where I find that some girls actually act scared of me. The best example would be in my workplace. Generally I am well known at work, I dont have any enemies, I keep myself to myself usually, and generally get on with everyone.

Now of course I am friends with some female co-workers and have no problem with them. My problem is is that around 4 or 5 girls in my workplace have never spoken to me, or even made eye contact with me. If I walk past them in a corridor they will look straight at the ground, look awkward and sometimes even walk as close to the wall as possible. Ive even tried to say hi to some of them but I get no response except an uncomfortable expression. and also i must mention that I have worked around some of these girls for a number of years. They have been around when ive been laughing and joking with other people so they should be able to see I'm not a threat.

It has also happened outside of work aswell, when I walk past girls on the street. I dont say hi to random strangers but sometimes i'll try and give a smile.

Ive read someother stuff on the web where men have had the same problem and generally the solution to their problems are clear. But I am generally a normal guy, I dress normally, I do my best to have a friendly, natural smile. I do not stare at girls, i'll just try and make regular natural eye-contact.

Could it just be that i'm ugly? I know as a rule women generally find ugly men naturally creepy, but i never thought i was that unnattractive. If anyone could shed some light I would be so grateful as it is absolutely destroying my confidence and self-esteem.

thank you
Ill try and include a link to a pic of me so u can judge for yourselves.
https://twitter.com/Benjy_NMG/status/496749573948575744/photo/1