When we deploy a web part, we can find it on any pages through the follow steps:
Firstly, go to one page, change to the “Pages” tabs, and click “Edit”, you will find a “Insert” tab appear on the menu. Then click
“Insert” and select “Web Parts”,
You will find your web part in the “Custom” group.
And select your web part, click “Add”, then the web part will be added on the page. You can use it now. Don’t forget click “Save”
to save your web part when you leave this page.
But sometimes, when you do these steps, you will not find your web part in the “Custom” group. Then you can check as the
follows steps:
Firstly, unzip the .wsp file, check whether the web part is in the file. If not, it means your web part doesn’t package in the file
when you complier the solution.
Secondly, if you find your web part in the .wsp file, and the feature is activated. Then go to the site “Home” click “Site setting”,
select the “Web Part” in the “Web Designer Galleries” group.
If you find your web part, then check if your web part is in the “Custom” group, if not, click “Edit” and set it in the “Custom”
group.
And if you still don’t find your web part, go to the “FILES” tab and click “New Document”
In the pages, you may be finding your web part. If you get it, select it and click “Populate Gallery”, it will be in the web part list.
And you should edit it in the web part list,change the group to “Custom”. Then you can find your web part through the normal
steps. But if you don’t find your web part when you click “New Document”, there is no way I know to help you. It may be have
something wrong when you build the web part.
Reference：SharePoint 2010部署项目后找不到WebPart的解决办法