I assume you mean DivX Plus HD? If so....
If you open the x264 encoder dialogue, reset it to defaults, then select DivX Plus HD as the target playback device, is the end result the same as the old profile?
If not, here's an old version I have saved, although the profiles did tend to be modified over time and I don't know how old this is. The file itself is named "x264_dp_ DivX Plus HD.xml"
<?xml version="1.0"?>
<GenericProfileOfx264Settings xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<Name>DivX Plus HD</Name>
<Settings>
<EncodingMode>9</EncodingMode>
<BitrateQuantizer>20</BitrateQuantizer>
<KeyframeInterval>95</KeyframeInterval>
<NbBframes>3</NbBframes>
<MinQuantizer>0</MinQuantizer>
<MaxQuantizer>51</MaxQuantizer>
<V4MV>false</V4MV>
<QPel>false</QPel>
<Trellis>false</Trellis>
<CreditsQuantizer>40</CreditsQuantizer>
<Logfile>.stats</Logfile>
<VideoName />
<CustomEncoderOptions>--vbv-maxrate 20000 --vbv-bufsize 25000 --level 40 --bframes 3 --qpmax 51</CustomEncoderOptions>
<FourCC>0</FourCC>
<MaxNumberOfPasses>3</MaxNumberOfPasses>
<NbThreads>0</NbThreads>
<x264PresetLevel>medium</x264PresetLevel>
<x264Tuning>0</x264Tuning>
<QuantizerCRF>20</QuantizerCRF>
<InterlacedMode>progressive</InterlacedMode>
<TargetDeviceXML>0</TargetDeviceXML>
<BlurayCompatXML>False</BlurayCompatXML>
<NoDCTDecimate>false</NoDCTDecimate>
<PSNRCalculation>false</PSNRCalculation>
<NoFastPSkip>false</NoFastPSkip>
<NoiseReduction>0</NoiseReduction>
<NoMixedRefs>false</NoMixedRefs>
<X264Trellis>1</X264Trellis>
<NbRefFrames>3</NbRefFrames>
<AlphaDeblock>0</AlphaDeblock>
<BetaDeblock>0</BetaDeblock>
<SubPelRefinement>7</SubPelRefinement>
<MaxQuantDelta>4</MaxQuantDelta>
<TempQuantBlur>0</TempQuantBlur>
<BframePredictionMode>1</BframePredictionMode>
<VBVBufferSize>25000</VBVBufferSize>
<VBVMaxBitrate>20000</VBVMaxBitrate>
<METype>1</METype>
<MERange>16</MERange>
<MinGOPSize>9</MinGOPSize>
<IPFactor>1.4</IPFactor>
<PBFactor>1.3</PBFactor>
<ChromaQPOffset>0</ChromaQPOffset>
<VBVInitialBuffer>0.9</VBVInitialBuffer>
<BitrateVariance>1.0</BitrateVariance>
<QuantCompression>0.6</QuantCompression>
<TempComplexityBlur>20</TempComplexityBlur>
<TempQuanBlurCC>0.5</TempQuanBlurCC>
<SCDSensitivity>40</SCDSensitivity>
<BframeBias>0</BframeBias>
<PsyRDO>1.0</PsyRDO>
<PsyTrellis>0</PsyTrellis>
<Deblock>true</Deblock>
<Cabac>true</Cabac>
<UseQPFile>false</UseQPFile>
<WeightedBPrediction>true</WeightedBPrediction>
<WeightedPPrediction>2</WeightedPPrediction>
<NewAdaptiveBFrames>1</NewAdaptiveBFrames>
<x264BFramePyramid>2</x264BFramePyramid>
<ChromaME>true</ChromaME>
<MacroBlockOptions>3</MacroBlockOptions>
<P8x8mv>true</P8x8mv>
<B8x8mv>true</B8x8mv>
<I4x4mv>true</I4x4mv>
<I8x8mv>true</I8x8mv>
<P4x4mv>false</P4x4mv>
<AdaptiveDCT>true</AdaptiveDCT>
<SSIMCalculation>false</SSIMCalculation>
<QuantizerMatrix>Flat (none)</QuantizerMatrix>
<QuantizerMatrixType>0</QuantizerMatrixType>
<DeadZoneInter>21</DeadZoneInter>
<DeadZoneIntra>11</DeadZoneIntra>
<OpenGop>False</OpenGop>
<X264PullDown>0</X264PullDown>
<SampleAR>0</SampleAR>
<ColorMatrix>0</ColorMatrix>
<ColorPrim>0</ColorPrim>
<Transfer>0</Transfer>
<AQmode>1</AQmode>
<AQstrength>1.0</AQstrength>
<QPFile>.qpf</QPFile>
<fullRange>false</fullRange>
<x264AdvancedSettings>false</x264AdvancedSettings>
<Lookahead>40</Lookahead>
<NoMBTree>true</NoMBTree>
<ThreadInput>true</ThreadInput>
<NoPsy>false</NoPsy>
<Scenecut>true</Scenecut>
<Nalhrd>0</Nalhrd>
<X264Aud>false</X264Aud>
<X264SlowFirstpass>false</X264SlowFirstpass>
<PicStruct>false</PicStruct>
<FakeInterlaced>false</FakeInterlaced>
<NonDeterministic>false</NonDeterministic>
<SlicesNb>0</SlicesNb>
<MaxSliceSyzeBytes>0</MaxSliceSyzeBytes>
<MaxSliceSyzeMBs>0</MaxSliceSyzeMBs>
<Profile>2</Profile>
<Level>10</Level>
</Settings>
</GenericProfileOfx264Settings>