diff --git a/src/QEQ/fix_qeq_point.h b/src/QEQ/fix_qeq_point.h
index db70444311..eae9603bf5 100644
--- a/src/QEQ/fix_qeq_point.h
+++ b/src/QEQ/fix_qeq_point.h
@@ -56,6 +56,8 @@ This is the size of the matrix.
 
 E: Fix qeq/point has insufficient QEq matrix size
 
-UNDOCUMENTED
+Occurs when number of neighbor atoms for an atom increased too much
+during a run.  Increase SAFE_ZONE and MIN_CAP in fix_qeq.h and
+recompile.
 
 */
diff --git a/src/QEQ/fix_qeq_shielded.h b/src/QEQ/fix_qeq_shielded.h
index 73ff7b05fd..f9e1e0172e 100644
--- a/src/QEQ/fix_qeq_shielded.h
+++ b/src/QEQ/fix_qeq_shielded.h
@@ -74,6 +74,8 @@ This is the size of the matrix.
 
 E: Fix qeq/shielded has insufficient QEq matrix size
 
-UNDOCUMENTED
+Occurs when number of neighbor atoms for an atom increased too much
+during a run.  Increase SAFE_ZONE and MIN_CAP in fix_qeq.h and
+recompile.
 
 */
diff --git a/src/QEQ/fix_qeq_slater.h b/src/QEQ/fix_qeq_slater.h
index 71754b94e9..bf1a98a6d5 100644
--- a/src/QEQ/fix_qeq_slater.h
+++ b/src/QEQ/fix_qeq_slater.h
@@ -79,6 +79,8 @@ This is the size of the matrix.
 
 E: Fix qeq/slater has insufficient QEq matrix size
 
-UNDOCUMENTED
+Occurs when number of neighbor atoms for an atom increased too much
+during a run.  Increase SAFE_ZONE and MIN_CAP in fix_qeq.h and
+recompile.
 
 */
diff --git a/src/fix_ave_chunk.cpp b/src/fix_ave_chunk.cpp
index 881ea69b15..921c6863e0 100644
--- a/src/fix_ave_chunk.cpp
+++ b/src/fix_ave_chunk.cpp
@@ -298,7 +298,8 @@ FixAveChunk::FixAveChunk(LAMMPS *lmp, int narg, char **arg) :
 
   // increment lock counter in compute chunk/atom
   // only if nrepeat > 1 or ave = RUNNING/WINDOW,
-  //  so that locking spans multiple timesteps 
+  //   so that locking spans multiple timesteps 
+  // set lock here for ave = RUN/WINDOW or in end_of_step() for nrepeat > 1
 
   int icompute = modify->find_compute(idchunk);
   if (icompute < 0)
@@ -308,7 +309,10 @@ FixAveChunk::FixAveChunk(LAMMPS *lmp, int narg, char **arg) :
     error->all(FLERR,"Fix ave/chunk does not use chunk/atom compute");
 
   if (nrepeat > 1 || ave == RUNNING || ave == WINDOW) cchunk->lockcount++;
-  if (ave == RUNNING || ave == WINDOW) cchunk->lock(this,update->ntimestep,-1);
+  if (ave == RUNNING || ave == WINDOW) {
+    nchunk = cchunk->setup_chunks();
+    cchunk->lock(this,update->ntimestep,-1);
+  }
 
   // print file comment lines
 
@@ -533,7 +537,7 @@ void FixAveChunk::end_of_step()
       modify->addstep_compute(ntimestep+nfreq);
     }
     allocate();
-    if (nrepeat > 1 && ave == ONE) 
+    if (nrepeat > 1 && ave == ONE)
       cchunk->lock(this,ntimestep,ntimestep+(nrepeat-1)*nevery);
     for (m = 0; m < nchunk; m++) {
       count_many[m] = count_sum[m] = 0.0;
diff --git a/src/fix_ave_time.cpp b/src/fix_ave_time.cpp
index 0bbaee5af5..b749a19425 100644
--- a/src/fix_ave_time.cpp
+++ b/src/fix_ave_time.cpp
@@ -274,7 +274,11 @@ FixAveTime::FixAveTime(LAMMPS *lmp, int narg, char **arg) :
   }
   
   // enable locking of row count by this fix for computes of variable length
-  // only if nrepeat > 1, so that locking spans multiple timesteps 
+  // only if nrepeat > 1 or ave = RUNNING/WINDOW,
+  //   so that locking spans multiple timesteps 
+  // trigger lock_length here for ave = RUN/WINDOW
+  //   or in end_of_step() for nrepeat > 1,
+  //   so that row count = number of chunks is set
 
   if (any_variable_length && 
       (nrepeat > 1 || ave == RUNNING || ave == WINDOW)) {
@@ -282,8 +286,10 @@ FixAveTime::FixAveTime(LAMMPS *lmp, int narg, char **arg) :
       if (varlen[i]) {
         int icompute = modify->find_compute(ids[i]);
         modify->compute[icompute]->lock_enable();
-        if (ave == RUNNING || ave == WINDOW) 
+        if (ave == RUNNING || ave == WINDOW) {
+          modify->compute[icompute]->lock_length();
           modify->compute[icompute]->lock(this,update->ntimestep,-1);
+        }
       }
   }