External Tool not appearing revit 2019

[Mohamed.E.Salem]

hi my friends ,

the external tools button does not show up on my update of Revit 2019 . I tried to use the Revit Platform API and C# to create a Hello World program. I followed all steps in the API help "Walkthrough: Hello World".

http://help.autodesk.com/view/RVT/2019/ENU/?guid=Revit_API_Revit_API_Developers_Guide_Introduction_G...

I have read throught the forums .but , i can't find a solution. anyone can help.

[stever66]

Although these were VB.net, check these two threads;

https://forums.autodesk.com/t5/revit-api-forum/class-cannot-be-found-in-the-addin-assembly-vb-net/td...

and this:

https://forums.autodesk.com/t5/revit-api-forum/my-add-in-application-vb-net-doesn-t-appear-on-addins...

If you get no error message when revit starts, and revit doesn't ask if you want to load the .dll file, it probably isn't reading the manifest file.   Most common cause is that Notepad is adding a .txt on the end of the filename.  You have to check the file name in windows file explorer, and to do that, you have to make sure windows file explorer is set to show all file extensions. 

[BIM.Frankliang]

Hi Friend,

     You may check your .addin file or you could post your addin file as attachment, so we can help you to find out reason. Wish it is helpful 🙂

Best Regards,

Frank Liang

[Mohamed.E.Salem]

The addin file may be helpfull

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<td class="entry" valign="top"><b>Code Region 2-2: Creating a .addin manifest file for an external command</b>

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<pre class="pre codeblock prettyprint"><?xml version="1.0" encoding="utf-8" standalone="no"?>
<RevitAddIns>
        <AddIn Type="Command">
                <Assembly>C:\Users\Mohamed\source\repos\HelloWord\HelloWord\bin\Debug\HelloWord.dll</Assembly>
                <AddInId>9F4529BD-9FA8-4714-BA38-2E49BC64E7F0</AddInId>
                <FullClassName>HelloWorld.Class1</FullClassName>
                <Text>HelloWorld</Text> 
                <VendorId>mohamed</VendorId>
                <VendorDescription>salemgroup</VendorDescription> 
        </AddIn>
</RevitAddIns></pre>

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