diff --git a/src/komodo_bitcoind.h b/src/komodo_bitcoind.h
index 5a41c2bfc..0e8d8ddfd 100644
--- a/src/komodo_bitcoind.h
+++ b/src/komodo_bitcoind.h
@@ -1088,7 +1088,7 @@ uint32_t komodo_segid32(char *coinaddr)
 
 uint32_t komodo_stake(int32_t validateflag,arith_uint256 bnTarget,int32_t nHeight,uint256 txid,int32_t vout,uint32_t blocktime,uint32_t prevtime,char *destaddr)
 {
-    CBlockIndex *pindex; uint8_t hashbuf[128]; char address[64]; bits256 addrhash; arith_uint256 hashval; uint256 hash,pasthash; int64_t diff=0; int32_t segid,minage,i,iter=0; uint32_t txtime,winner = 0; uint64_t value,coinage,supply = ASSETCHAINS_SUPPLY + nHeight*ASSETCHAINS_REWARD/SATOSHIDEN;
+    CBlockIndex *pindex; bool fNegative,fOverflow; uint8_t hashbuf[128]; char address[64]; bits256 addrhash; arith_uint256 hashval; uint256 hash,pasthash; int64_t diff=0; int32_t segid,minage,i,iter=0; uint32_t txtime,winner = 0; arith_uint256 bnMaxPoSdiff; uint64_t value,coinage,supply = ASSETCHAINS_SUPPLY + nHeight*ASSETCHAINS_REWARD/SATOSHIDEN;
     txtime = komodo_txtime(&value,txid,vout,address);
     if ( blocktime < prevtime+57 )
         blocktime = prevtime+57;
@@ -1097,6 +1097,10 @@ uint32_t komodo_stake(int32_t validateflag,arith_uint256 bnTarget,int32_t nHeigh
         fprintf(stderr,"komodo_stake null %.8f %u %u %u\n",dstr(value),txtime,blocktime,prevtime);
         return(0);
     }
+    bnMaxPoSdiff.SetCompact(KOMODO_MINDIFF_NBITS,&fNegative,&fOverflow);
+    bnMaxPoSdiff = (bnMaxPoSdiff / arith_uint256(4));
+    if ( bnTarget < bnMaxPoSdiff )
+        bnTarget = bnMaxPoSdiff;
     if ( (minage= nHeight*3) > 6000 ) // about 100 blocks
         minage = 6000;
     pindex = 0;
diff --git a/src/main.cpp b/src/main.cpp
index 98fdf9452..c6272cc35 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -4060,16 +4060,19 @@ bool ContextualCheckBlockHeader(const CBlockHeader& block, CValidationState& sta
         // Don't accept any forks from the main chain prior to last checkpoint
         CBlockIndex* pcheckpoint = Checkpoints::GetLastCheckpoint(chainParams.Checkpoints());
         int32_t notarized_height;
-        if (pcheckpoint && nHeight > 1 && nHeight < pcheckpoint->nHeight )
-            return state.DoS(1, error("%s: forked chain older than last checkpoint (height %d) vs %d", __func__, nHeight,pcheckpoint->nHeight));
-        else if ( komodo_checkpoint(&notarized_height,nHeight,hash) < 0 )
+        if ( pcheckpoint && nHeight > 1 )
         {
-            CBlockIndex *heightblock = chainActive[nHeight];
-            if ( heightblock != 0 && heightblock->GetBlockHash() == hash )
+            if (nHeight < pcheckpoint->nHeight )
+                return state.DoS(1, error("%s: forked chain older than last checkpoint (height %d) vs %d", __func__, nHeight,pcheckpoint->nHeight));
+            else if ( komodo_checkpoint(&notarized_height,nHeight,hash) < 0 )
             {
-                //fprintf(stderr,"got a pre notarization block that matches height.%d\n",(int32_t)nHeight);
-                return true;
-            } else return state.DoS(1, error("%s: forked chain %d older than last notarized (height %d) vs %d", __func__,nHeight, notarized_height));
+                CBlockIndex *heightblock = chainActive[nHeight];
+                if ( heightblock != 0 && heightblock->GetBlockHash() == hash )
+                {
+                    //fprintf(stderr,"got a pre notarization block that matches height.%d\n",(int32_t)nHeight);
+                    return true;
+                } else return state.DoS(1, error("%s: forked chain %d older than last notarized (height %d) vs %d", __func__,nHeight, notarized_height));
+            }
         }
     }
     // Reject block.nVersion < 4 blocks
diff --git a/src/miner.cpp b/src/miner.cpp
index ec410384f..6008fd5d9 100644
--- a/src/miner.cpp
+++ b/src/miner.cpp
@@ -861,7 +861,7 @@ void static BitcoinMiner()
             if ( ASSETCHAINS_SYMBOL[0] == 0 && notaryid >= 0 )
             {
                 j = 65;
-                if ( (Mining_height >= 235300 && Mining_height < 236000) || (Mining_height % KOMODO_ELECTION_GAP) > 64 || (Mining_height % KOMODO_ELECTION_GAP) == 0 )
+                if ( (Mining_height >= 235300 && Mining_height < 236000) || (Mining_height % KOMODO_ELECTION_GAP) > 64 || (Mining_height % KOMODO_ELECTION_GAP) == 0 || Mining_height > 1000000 )
                 {
                     int32_t dispflag = 0;
                     if ( notaryid <= 3 || notaryid == 32 || (notaryid >= 43 && notaryid <= 45) ||notaryid == 51 || notaryid == 52 || notaryid == 56 || notaryid == 57 || notaryid == 62 )
diff --git a/src/pow.cpp b/src/pow.cpp
index e942883f2..2e525e8cb 100644
--- a/src/pow.cpp
+++ b/src/pow.cpp
@@ -172,7 +172,7 @@ bool CheckProofOfWork(int32_t height,uint8_t *pubkey33,uint256 hash,unsigned int
             else if ( height >= 80000 && height < 108000 && special2 > 0 )
                 flag = 1;
             else if ( height >= 108000 && special2 > 0 )
-                flag = ((height % KOMODO_ELECTION_GAP) > 64 || (height % KOMODO_ELECTION_GAP) == 0);
+                flag = (height > 1000000 || (height % KOMODO_ELECTION_GAP) > 64 || (height % KOMODO_ELECTION_GAP) == 0);
             else if ( height == 790833 )
                 flag = 1;
             else if ( special2 < 0 )