I was getting the unsafe Web Part error trying to drag the EasyTabParts.wssv3 web part onto a page.
(http://www.gotdotnet.com/Community/UserSamples/Details.aspx?SampleGuid=ef23da8a-72b6-4a04-b536-46da24b2605b)
(http://www.divshare.com/download/1761708-c06)
Normally, the unsafe web part error occurs because the file is not registered as safe in the web.config, or all the files are not properly in place (such as a missing dll). So I tried to clean and reinstall first.
In my efforts to migrate from SharePoint 2003 to MOSS 2007, there was some "residue" that I needed to get rid of from the 2003 version.
I performed the following steps to clean and reinstall:
cd C:\Program Files\Common Files\Microsoft Shared\web server extensions\12\BIN
stsadm -o enumwppacks
stsadm -o deletewppack -name easytabpartsdeployment.cab
C:\WINDOWS\assembly
Uninstall EasyTabParts
cd C:\Program Files\Common Files\Microsoft Shared\web server extensions\12\BIN
stsadm -o addwppack -filename EasyTabPartsDeployment.cab -globalinstall -url http://sps01:83/
iisreset
Then I started to get a new error trying to drag the web part onto the page:
Cannot add Web Part to the Web Part Page. For more assistance, contact your site administrator.
Then I copied the dll into the web site's bin directory.
copy EasyTabParts.dll C:\Inetpub\wwwroot\wss\VirtualDirectories\83\bin
After that, the web part could be dragging onto the page without errors.