Solidify doesn't work

The solidify tool does not work properly for me. It just produces very strange deformation and random vertices everywhere. I’ve looked online and a lot of people are sharing the same problem, but no one has a solution that worked for me. Can someone help? Edit: It won’t let me upload attachments, so I’ll put one in dropbox.

If you check Face orientation you’ll see what’s happening.

Edit mode select all and Shift+N to recalculate Normals.

Could easily and fairly be considered a off topic post, but …

@bartv I’m going to make a case for having couple of tags added for different blender versions since based on OP it’s hard to tell what version opening poster is using and accordingly what advice to give. Previous poster assumes, potentially correctly, 2.80(there’s a tag for this one only). But it could be 2.79 or for all we know 2.49 even that the OP is using.

We have a tag for 2.8. Anything else can be assumed to be 2.79 or lower.

If hes using 2.49 then im sure he’d specify as its extremely rare.