How do I update parts of my Avatar, so items show correctly again?

[Rolig Loon]

You are probably wearing hair that comes with an alpha layer.  You may have already discovered that mesh hair tends to look less distinct and show gaps as you look at it from a distance.  That is normal behavior, a consequence of the Level of Detail (LOD) system that is built into all mesh objects.  The alpha layer is provided so that you do not see your bald skull as that LOD degradation occurs.  The downside, of course, is that instead of seeing a bald head, you see a hole.  Personally, I prefer to go without the alpha layer or (even better) to wear non-mesh hair, which doesn't do that.  :smileywink:

[Rolig Loon]

You are probably wearing hair that comes with an alpha layer.  You may have already discovered that mesh hair tends to look less distinct and show gaps as you look at it from a distance.  That is normal behavior, a consequence of the Level of Detail (LOD) system that is built into all mesh objects.  The alpha layer is provided so that you do not see your bald skull as that LOD degradation occurs.  The downside, of course, is that instead of seeing a bald head, you see a hole.  Personally, I prefer to go without the alpha layer or (even better) to wear non-mesh hair, which doesn't do that.  :smileywink:

[angeoco]

Your hair may be badly positioned. If the hair has modify permission you might be able to reposition it - right-click the hair, select Edit, and a set of positioning arrows will appear; drag the arrows until it looks right, or adjust the figures in the dialogue box. Or it may have a resize menu - click the hair and select the appropriate options on the blue menu.

[Lindal Kidd]

When you get an update from a creator, it's usually boxed.  I'm assuming you know how to open a box and transfer its contents into your inventory.  If not, see: https://community.secondlife.com/knowledgebase/english/opening-boxes-r84/

In the case of an alpha layer (which is what's making part of your head invisible), first find the old alpha layer that you are wearing.  In your inventory, search for (WORN [yes, with the left parenthesis] or if you use Firestorm, check the Worn tab.  Right click the item and select Take Off or Remove from Current Outfit.

Then right click the new alpha layer item you unpacked and select ADD.

 

[Nalates Urriah]

Everyone is guessing. Good guesses, but guesses. They may by luck be right.

If the answers do not get your problem resolved, you need to give us more information so we do not have to guess. A picture would help. A more precise description of the 'something' given for an update...