TMPEGENC不認得VDR檔的原因並不在這些步驟
列出以下幾點可能
1.安裝VIRTUALDUB是否有執行過AUXSETUP.EXE並選取INSTALL HANDLER
2.VIRTUALDUB資料夾下的PROXY資料夾下有兩個REG檔，PROXYON跟PROXYOFF

The AVIFile handler included with VirtualDub 1.3b is capable
of running in Proxy mode -- that is, you can install it as the
*default* handler for AVI files, and it will work with signposts
that are renamed to the AVI extension. This means that
applications which previously failed with the AVIFile handler
because of the .VDR extension can now be used, provided that
the .VDR files are renamed to the .AVI extension.

This support is very experimental, so try at your own risk.

To try the AVIFile proxy support, first use auxsetup.exe to
install AVIFile frameserver support, then use the REGEDIT tool
to install the proxyon.reg file. Use the proxyoff.reg file
to disable it.

The proxy support will be invisible to most programs, but some
programs do not like the proxy handler and will no longer work
if it is installed; you will have to disable the proxy for
these programs. These applications were tested:

Ligos LSX-MPEG Encoder 3.0: works
Panasonic MPEG Encoder 2.30: works most of the time
XingMPEG Encoder 2.20: fails (must deinstall proxy)

這段文字是該資料夾下的說明檔
由以上文字這兩個REG檔是作為關閉或開關VDR檔的作用
因為有部分軟體對VIRTUALDUB的VDR檔感冒，如AVISYNTH等
3.如以上方法皆不行，可以靠VIRTUALDUB GATEWAY這個小工具
他是將VDR轉化成VFAPI相容的介面，界以上TMPEGENC與AVIUTL等支援VFAPI的VIDEO處理程式可以認得VDR檔
安裝完後在TMPEGENC的VFAPI PLUGIN裡會多出一個VIRTUALDUB GATEWAY

4.VDR的檔名跟目錄請勿過長

很多人解開VIRTUALDUB即開始執行主程式，而漏掉了AUXSETUP的安裝動作

請檢查你的流程是否正確