diff --git a/src/org/rascalmpl/core/library/lang/rascalcore/check/Checker.rsc b/src/org/rascalmpl/core/library/lang/rascalcore/check/Checker.rsc
index ba5da4b1..b1e28aba 100644
--- a/src/org/rascalmpl/core/library/lang/rascalcore/check/Checker.rsc
+++ b/src/org/rascalmpl/core/library/lang/rascalcore/check/Checker.rsc
@@ -130,8 +130,8 @@ ModuleStatus rascalTModelForLocs(
 
     for (mloc <- mlocs) {
         m = getModuleName(mloc, pcfg);
-        if(isModuleLocationInLibs(mloc, pcfg)){
-            ms.status[m] ? {} += rsc_not_found();
+        if(isModuleLocationInLibs(m, mloc, pcfg)){
+            ms.status[m] ? {} += {rsc_not_found()};
         }
         topModuleNames += {m};
         ms.moduleLocs[m] = mloc;
@@ -186,6 +186,9 @@ ModuleStatus rascalTModelForLocs(
 
         while(mi < nmodules) {
             component = module2component[ordered[mi]];
+            if(component == {"IO"}){
+                println("IO");
+            }
             jobStep(jobName, intercalate(" + ", [*component]), work=size(component));
 
             recheck = !all(m <- component, ms.status[m]?, (tpl_uptodate() in ms.status[m] || checked() in ms.status[m]));
@@ -382,7 +385,7 @@ tuple[TModel, ModuleStatus] rascalTModelComponent(set[str] moduleNames, ModuleSt
         ms.status[nm] = {};
         ms.messages[nm] = [];
         mloc = getModuleLocation(nm, pcfg);
-        if(mloc.extension != "rsc" || isModuleLocationInLibs(mloc, pcfg)){
+        if(mloc.extension != "rsc" || isModuleLocationInLibs(nm, mloc, pcfg)){
             continue;
         }
         <success, pt, ms> = getModuleParseTree(nm, ms);
diff --git a/src/org/rascalmpl/core/library/lang/rascalcore/check/CheckerCommon.rsc b/src/org/rascalmpl/core/library/lang/rascalcore/check/CheckerCommon.rsc
index 9e0d37cc..2a60e38b 100644
--- a/src/org/rascalmpl/core/library/lang/rascalcore/check/CheckerCommon.rsc
+++ b/src/org/rascalmpl/core/library/lang/rascalcore/check/CheckerCommon.rsc
@@ -73,8 +73,11 @@ data ModuleStatus =
 
 ModuleStatus newModuleStatus(RascalCompilerConfig ccfg) = moduleStatus({}, {}, (), [], (), [], (), (), (), (), ccfg.typepalPathConfig, ccfg);
 
-bool isModuleLocationInLibs(loc l, PathConfig pcfg)
-    = !isEmpty(pcfg.libs) && any(lib <- pcfg.libs, l.scheme == lib.scheme && l.path == lib.path);
+bool isModuleLocationInLibs(str mname, loc l, PathConfig pcfg){
+    res = l.extension == "tpl" || !isEmpty(pcfg.libs) && any(lib <- pcfg.libs, l.scheme == lib.scheme && l.path == lib.path);
+    //println("isModuleLocationInLibs: <mname>, <l> ==\> <res>");
+    return res;
+}
 
 bool traceTPL = false;
 bool traceParseTreeCache = false;
@@ -148,7 +151,7 @@ tuple[bool, Module, ModuleStatus] getModuleParseTree(str qualifiedModuleName, Mo
             try {
                 mloc = getModuleLocation(qualifiedModuleName, pcfg);
                 // Make sure we found a real source module (as opposed to a tpl module in a library
-                if(mloc.extension != "rsc" || isModuleLocationInLibs(mloc, pcfg)) {
+                if(isModuleLocationInLibs(qualifiedModuleName, mloc, pcfg)) {
                     ms.status[qualifiedModuleName] += {rsc_not_found()};
                     throw "No src or library module";
                 }
@@ -286,8 +289,12 @@ tuple[bool, TModel, ModuleStatus] getTModelForModule(str qualifiedModuleName, Mo
         try {
             tpl = readBinaryValueFile(#TModel, tplLoc);
             if(tpl.rascalTplVersion? && isValidRascalTplVersion(tpl.rascalTplVersion)){
+                tpl.convertedToPhysical = false; // temporary
                 tpl = convertTModel2PhysicalLocs(tpl);
-
+                mloc = getModuleLocation(qualifiedModuleName, pcfg);
+                if(isModuleLocationInLibs(qualifiedModuleName, mloc, pcfg)){
+                    ms.status[qualifiedModuleName] ? {} += rsc_not_found();
+                }
                 ms.tmodels[qualifiedModuleName] = tpl;
                 ms.status[qualifiedModuleName] ? {} += {tpl_uptodate(), tpl_saved()};
                 if(qualifiedModuleName notin hardwired){
diff --git a/src/org/rascalmpl/core/library/lang/rascalcore/check/Import.rsc b/src/org/rascalmpl/core/library/lang/rascalcore/check/Import.rsc
index 2abfeda4..231340ab 100644
--- a/src/org/rascalmpl/core/library/lang/rascalcore/check/Import.rsc
+++ b/src/org/rascalmpl/core/library/lang/rascalcore/check/Import.rsc
@@ -132,7 +132,7 @@ ModuleStatus getImportAndExtendGraph(str qualifiedModuleName, ModuleStatus ms){
         if(!allImportsAndExtendsValid){ // Check that the source code of qualifiedModuleName is available
             try {
                 mloc = getModuleLocation(qualifiedModuleName, pcfg);
-                if(mloc.extension != "rsc" || isModuleLocationInLibs(mloc, pcfg)) throw "No src or library module 1"; //There is only a tpl file available
+                if(mloc.extension != "rsc" || isModuleLocationInLibs(qualifiedModuleName, mloc, pcfg)) throw "No src or library module 1"; //There is only a tpl file available
             } catch value _:{
                 <compatible, ms> = isCompatibleBinaryLibrary(tm, domain(localImportsAndExtends), ms);
                 if(!compatible){
@@ -259,7 +259,7 @@ tuple[ModuleStatus, rel[str, PathRole, str]] getModulePathsAsStr(Module m, Modul
         ms.status[iname] = ms.status[iname] ? {};
         try {
             mloc = getModuleLocation(iname, ms.pathConfig);
-            //if(mloc.extension != "rsc" || isModuleLocationInLibs(mloc, ms.pathConfig)) throw "No src or library module 2";
+            //if(mloc.extension != "rsc" || isModuleLocationInLibs(iname, mloc, ms.pathConfig)) throw "No src or library module 2";
          } catch str msg: {
             ms.messages[moduleName] ? [] += [ error(msg, imod@\loc) ];
             ms.status[iname] += { rsc_not_found() };
@@ -332,6 +332,9 @@ rel[str,datetime,PathRole] makeBom(str qualifiedModuleName, set[str] imports, se
            + { <qualifiedModuleName, getLastModified(qualifiedModuleName, moduleLastModified, pcfg), importPath() > };
 }
 void updateBOM(str qualifiedModuleName, set[str] imports, set[str] extends,  ModuleStatus ms){
+    if(isModuleLocationInLibs(qualifiedModuleName, ms.moduleLocs[qualifiedModuleName], ms.pathConfig)){
+        return;
+    }
     <found, tm, ms> = getTModelForModule(qualifiedModuleName, ms);
     if(found){
         newBom = makeBom(qualifiedModuleName, imports, extends, ms);
@@ -451,6 +454,7 @@ ModuleStatus doSaveModule(set[str] component, map[str,set[str]] m_imports, map[s
                     case loc l : if(!isEmpty(l.fragment)) insert l[fragment=""];
                  };
 
+            m1.convertedToPhysical = false;
             ms.status[qualifiedModuleName] -= {tpl_saved()};
             ms = addTModel(qualifiedModuleName, m1, ms);
             //println("doSaveModule"); iprintln(m1.logical2physical);