diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index e596767d7..109ad2237 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -1266,8 +1266,15 @@ int CWallet::VerifyAndSetInitialWitness(const CBlockIndex* pindex, bool witnessO
         uint256 blockRoot;
         uint256 witnessRoot;
 
-        if (!nd->nullifier)
+        if (!nd->nullifier) {
           ::ClearSingleNoteWitnessCache(nd);
+          // A note found with only an incoming viewing key (z_importviewingkey) never gets a
+          // nullifier (UpdateSaplingNullifierNoteMapWithTx needs the full viewing key) and can't be
+          // spent, so it needs no witness. Building one re-read its block on every call and then
+          // aborted on *item.second.nullifier below.
+          if (!HaveSaplingFullViewingKey(nd->ivk))
+            continue;
+        }
 
         if (!nd->witnesses.empty() && nd->witnessHeight > 0) {
 
@@ -1358,7 +1365,10 @@ int CWallet::VerifyAndSetInitialWitness(const CBlockIndex* pindex, bool witnessO
         }
         nd->witnessHeight = pblockindex->GetHeight();
         UpdateSaplingNullifierNoteMapWithTx(wtxItem.second);
-        nMinimumHeight = SaplingWitnessMinimumHeight(*item.second.nullifier, nd->witnessHeight, nMinimumHeight);
+        if (item.second.nullifier)
+          nMinimumHeight = SaplingWitnessMinimumHeight(*item.second.nullifier, nd->witnessHeight, nMinimumHeight);
+        else
+          LogPrintf("%s: no witness found for note %s:%d in its block; it stays unspendable until a rescan\n", __func__, wtxHash.ToString(), op.n);
       }
     }
   }