Have you come across a situation where the Windows XP Search Companion window is completely blank, except for the search dog showing up at the bottom of the search pane? You can fix this problem by registering a couple of system DLLs.
If the Search Companion registration is broken, the Search window may be completely blank. In some cases it may default to Windows Classic search (which may work fine) even though the Search Companion is enabled.
Fixing Windows XP Search Companion User Interface
1. Login as Administrator or equivalent.
2. Click Start, Run. Execute the following commands:
You should see the message DllRegisterServer in <filename.dll> succeeded. for each DLL registered.
Logoff and login back (just in case the changes don’t take effect) and check if the Search Companion User Interface is displayed correctly. If it doesn’t, repair the search assistant components using Srchasst.inf.
Reinstalling the Search Companion using Srchasst.inf
Click Start, Run. Type %systemroot%\inf, and then click OK
Locate the file named SRCHASST.INF, right-click and choose Install. Note that the file extension (.INF) is not shown in Windows Explorer unless the Hide extensions for known file types setting is disabled in Control Panel / Folder Options / View tab.
In the next step, you’ll be asked for the Windows XP CD (to extract msgr3en.dll and other files). Insert your Windows XP CD and point to the i386 folder in the CD. The i386 folder is usually located at the root of the drive (e.g. E:\I386). However, if you’ve installed SP1/SP2 or SP3 separately after installing Windows XP, you need to point to the "%windir%\ServicePackFiles\i386" folder when prompted.
Search Companion is reinstalled now. Note that the above fixes don’t help resolve search index related issues.