C# WEB:Trouble converting videos on virtual directories using Windows Media Encoder 9

[clinnebur]

We have an ASP.NET web application (C#) that copies videos from a CCTV truck to a Linux server. What I am trying to do is convert the .AVI videos(which is how they are created on the truck) to .WMV in my C# code using Windows Media Encoder. I have a virtual directory to the truck location of the videos. I also have a virtual directory created to the Linux box. The application resides on a Windows Server 2003 and I am using VS 2005, .NET framework 2.0. The web app uses impersonation and the virtual directories are set up to connect with the impersonated user. When I use the application to copy the videos without converting, it works perfectly. When I try to implement the conversion code I receive the following error:

Attempted to read or write protected memory. This is often an indication that other memory has been corrupted

The line that fails is: m_Encoder.PrepareToEncode(true);

I have been Googling this error for days now and have found few solutions. I have tried some of the solutions I did manage to find, but nothing has helped. I'm thinking it's a permissions issue, but I can't figure out what! Any help would be greatly appreciated and please let me know if you need any more information. I am totally new to WME so I could even be doing this all wrong!
Thanks in Advance,
Carmen

Here is the code I'm using for the conversion and then the method where I am calling the ConvertFile function:

private static string ConvertFile(string mediaFile)
        {            
            UtilDaoOracle oraDao = new UtilDaoOracle();
            oraDao.LogError(mediaFile, "ConvertFile", 500321);
 
            WMEncoder m_Encoder = new WMEncoder();
 
            IWMEncSourceGroup SrcGrp = (IWMEncSourceGroup)m_Encoder.SourceGroupCollection.Add("SG_1");
            IWMEncVideoSource SrcVid = (IWMEncVideoSource)SrcGrp.AddSource(WMENC_SOURCE_TYPE.WMENC_VIDEO);
 
 
            SrcVid.SetInput(mediaFile, "", "");
 
            const string ProfileName = "Screen Video Medium (CBR)";
 
            foreach (IWMEncProfile aProfile in m_Encoder.ProfileCollection)
            {
                if (aProfile.Name == ProfileName)
                {
                    SrcGrp.set_Profile(aProfile);
                    oraDao.LogError(aProfile.Name.ToString(), "ConvertFileLoop", 500321);
                    break;
                }
            }
 
 
            m_Encoder.File.LocalFileName = Regex.Replace(mediaFile, ".avi", ".wmv");
            oraDao.LogError(m_Encoder.File.LocalFileName, "ConvertFileREturn", 500321);
 
            m_Encoder.AutoStop = true;
 
            try
            {
                m_Encoder.PrepareToEncode(true);
            }
            catch (Exception exp)
            {
                oraDao.LogError(exp.Message, "Preparetoencode", 500321);
                m_Encoder.Flush();
            }
 
            try
            {
                m_Encoder.Start();
            }
            catch (Exception exp)
            {
                oraDao.LogError(exp.Message, "encoderstart", 500321);
                m_Encoder.Flush();
            }
 
            return m_Encoder.File.LocalFileName;
 
        }
 
 
private static bool CopyFile(string srcDir, string destDir, string fileName, bool ignoreIfInParentDir)
        {
 
            UtilDaoOracle oraDao = new UtilDaoOracle();
            FileInfo destFile = new FileInfo(CombinePath(destDir, fileName));
 
            //Only copy if the file does not already exist.
            if (!destFile.Exists)
            {
                if (ignoreIfInParentDir && File.Exists(CombinePath(destFile.Directory.Parent.FullName, fileName)))
                {
                    // Return if the files already exists in the parent directory.
                    return false;
                }
 
                FileInfo srcFile = new FileInfo(CombinePath(srcDir, fileName));
                if (srcFile.Exists)
                {
                    // Create the destination directory if not there already.
                    if (!destFile.Directory.Exists)
                    {
                        destFile.Directory.Create();
                    }
 
                    if (srcFile.Extension == ".avi")
                    {
                        string convertedFile = ConvertFile(srcFile.ToString());
                        FileInfo convertedFileDone = new FileInfo(convertedFile);
                        convertedFileDone.CopyTo(destFile.FullName);                        
                    }
                    else
                    {
                        srcFile.CopyTo(destFile.FullName);
                    }
 
                    return true;
                }
                else
                {
                    Logger.LogWarning(string.Format("Source file not found on machine: {0}", srcFile.FullName));
                }
            }
            return false;
        }