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  <xs:element id="fsk_KKRCreditAdvisorsUSLLCMember" abstract="true" name="KKRCreditAdvisorsUSLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fsk_DebtInstrumentBorrowingRateTestThreshold" abstract="false" name="DebtInstrumentBorrowingRateTestThreshold" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="fsk_DebtInstrumentCovenantMinimumShareholdersEquityFloor" abstract="false" name="DebtInstrumentCovenantMinimumShareholdersEquityFloor" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fsk_NumberOfBusinessDaysAfterSaleOfStockToEnterTradingPlan" abstract="false" name="NumberOfBusinessDaysAfterSaleOfStockToEnterTradingPlan" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fsk_PreferredStockDiviendPayableCashPercentOfLiquidationPreferencePerShare" abstract="false" name="PreferredStockDiviendPayableCashPercentOfLiquidationPreferencePerShare" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fsk_PreferredStockDiviendPayableSharesPercentOfLiquidationPreferencePerShare" abstract="false" name="PreferredStockDiviendPayableSharesPercentOfLiquidationPreferencePerShare" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fsk_PreferredStockDiviendPayableProhibitedAdditionalSharesGreaterThanPreferredStockPercent" abstract="false" name="PreferredStockDiviendPayableProhibitedAdditionalSharesGreaterThanPreferredStockPercent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fsk_PreferredStockDividendRatePeriodUntilIncrease" abstract="false" name="PreferredStockDividendRatePeriodUntilIncrease" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fsk_PreferredStockPeriodUntilConvertible" abstract="false" name="PreferredStockPeriodUntilConvertible" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fsk_PreferredStockSharesEligibleToRedeemAtRedemptionPricePeriod" abstract="false" name="PreferredStockSharesEligibleToRedeemAtRedemptionPricePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fsk_PreferredStockNumberOfConsecutiveTradingDaysVolumeWeightedAverageSharePriceExceedsConversionPrice" abstract="false" name="PreferredStockNumberOfConsecutiveTradingDaysVolumeWeightedAverageSharePriceExceedsConversionPrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fsk_PreferredStockIssuerOptionRequiredRedemptionForCashPeriodAfterIssuance" abstract="false" name="PreferredStockIssuerOptionRequiredRedemptionForCashPeriodAfterIssuance" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fsk_PreferredStockIssuerOptionRequiredRedemptionForCashNoticePeriod" abstract="false" name="PreferredStockIssuerOptionRequiredRedemptionForCashNoticePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fsk_PreferredStockRestrictionOnSellingTransferOrDisposalPeriodFollowingIssuance" abstract="false" name="PreferredStockRestrictionOnSellingTransferOrDisposalPeriodFollowingIssuance" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fsk_PreferredStockConvertibleRightToElectMembersOfTheBoardNumber" abstract="false" name="PreferredStockConvertibleRightToElectMembersOfTheBoardNumber" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fsk_PreferredStockConvertibleBeneficialOwnershipPercentage" abstract="false" name="PreferredStockConvertibleBeneficialOwnershipPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fsk_PreferredStockConvertibleAccumulatedDividendsEqualToDividendsDueAndUnpaidNumberOfYears" abstract="false" name="PreferredStockConvertibleAccumulatedDividendsEqualToDividendsDueAndUnpaidNumberOfYears" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fsk_SaleOfStockCommonStockNYSEMinimumPriceNumberOfTradingDays" abstract="false" name="SaleOfStockCommonStockNYSEMinimumPriceNumberOfTradingDays" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fsk_PreferredStockRegistrationRightsAgreementNumberOfDemandRequestsMaximum" abstract="false" name="PreferredStockRegistrationRightsAgreementNumberOfDemandRequestsMaximum" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fsk_InvestmentCompanyIncentiveFeeWaivedPercent" abstract="false" name="InvestmentCompanyIncentiveFeeWaivedPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fsk_InvestmentCompanyIncentiveFeeWaivedPercentOfApplicableIncentiveFee" abstract="false" name="InvestmentCompanyIncentiveFeeWaivedPercentOfApplicableIncentiveFee" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
</xs:schema>
