Give this Query a go :
Select Top 1000000 tblAssets.AssetID,
tblAssets.AssetName,
tsysAssetTypes.AssetTypename,
tsysAssetTypes.AssetTypeIcon10 As icon,
tblAssets.IPAddress,
tblAssets.Lastseen,
tblAssets.Lasttried,
[User-Software].softwareName
From tblAssets
Inner Join tblAssetCustom On tblAssets.AssetID = tblAssetCustom.AssetID
Inner Join tsysAssetTypes On tsysAssetTypes.AssetType = tblAssets.Assettype
Inner Join (Select tblSoftware.CurrentUser,
tblSoftwareUni.softwareName,
tblSoftware.AssetID
From tblSoftware
Inner Join tblSoftwareUni On tblSoftwareUni.SoftID = tblSoftware.softID
Where tblSoftware.CurrentUser = 'true') [User-Software] On
[User-Software].AssetID = tblAssets.AssetID
Where tblAssetCustom.State = 1