diff --git a/README.md b/README.md
index 9ff349d..7dae8b3 100644
--- a/README.md
+++ b/README.md
@@ -33,7 +33,7 @@ depollueur/
 ## Compilation
 
 ```bash
-sudo apt-get install --fix-missing build-essential make g++ libboost-program-options-dev libboost-system-dev libboost-filesystem-dev libcurl4-gnutls-dev libssl-dev doxygen
+sudo apt-get install --fix-missing build-essential make g++ libboost-program-options-dev libboost-system-dev libboost-filesystem-dev libcurl4-gnutls-dev libssl-dev doxygen dos2unix
 
 git clone https://git.kaz.bzh/KAZ/depollueur.git
 # or for contributors :
diff --git a/src/bash/filterTest.sh b/src/bash/filterTest.sh
old mode 100755
new mode 100644
index d7560e0..e9ca941
--- a/src/bash/filterTest.sh
+++ b/src/bash/filterTest.sh
@@ -33,6 +33,7 @@ usage () {
 
 ########################################
 mbox=$(realpath $1)
+dos2unix "${mbox}"
 cd $(dirname $0)
 DOMAINNAME="$(cat domainname)"
 JIRAFEAU_URL="https://depot.${DOMAINNAME}"
@@ -126,7 +127,7 @@ cat "${TMP_DIR}/PJ-name.txt" | {
 	    esac
 	}
     else
-	LOG "  - ${GREEN} no archive${NC}"
+	LOG "  - ${GREEN}no archive${NC}"
 	echo "arch: none"
     fi
 } > "${TMP_DIR}/PJ-Keys.txt"
diff --git a/src/cpp/Attachment.cpp b/src/cpp/Attachment.cpp
index 1a2c755..9a365b9 100644
--- a/src/cpp/Attachment.cpp
+++ b/src/cpp/Attachment.cpp
@@ -60,8 +60,10 @@ const string Attachment::contentIDToken			("content-id");
 const string Attachment::PLAIN				("plain");
 const string Attachment::HTML				("html");
 const string Attachment::RELATED			("related");
+const string Attachment::SIGNED				("signed");
 const string Attachment::ALTERNATIVE			("alternative");
 const string Attachment::KAZ_ATTACH_NAME		(".---KazAttachment---.html");
+const string Attachment::MULTIPART			("multipart/");
 
 
 const regex Attachment::nameCharsetRegEx		(".*name\\*=[ \t]*(.*)");
@@ -76,7 +78,7 @@ const regex Attachment::nameRegEx			(".*name=[ \t]*((\"(\\\\.|[^\\\\\r])*\")|[^\
 const regex Attachment::boundaryRegEx			(".*boundary=[ \t]*((\"(\\\\.|[^\\\\])*\")|[^; ]*);?.*");
 const regex Attachment::cidDefRegEx			(".*<([^>]*)>.*");
 const regex Attachment::textRegEx			(".*text/("+PLAIN+"|"+HTML+").*");
-const regex Attachment::multiRegEx			("\\s*multipart/(mixed|"+RELATED+"|"+ALTERNATIVE+").*");
+const regex Attachment::multiRegEx			("\\s*"+MULTIPART+"(mixed|"+RELATED+"|"+ALTERNATIVE+"|"+SIGNED+").*");
 
 const string Attachment::IMG_BEGIN			("<IMG");
 const string Attachment::IMG_END			(">");
@@ -85,7 +87,6 @@ const string Attachment::IMG_END			(">");
 
 static const string SRC_BEGIN ("SRC=\"");
 static const string RFC822 ("message/rfc822");
-static const string MULTIPART ("multipart/");
 
 // ================================================================================
 string
@@ -270,6 +271,7 @@ Attachment::Attachment (ifstream &mbox, const int &level, const streamoff beginI
     toUpdate (false),
     toDisclaim (false),
     isKazAttachment (false),
+    isSigned (false),
     boundaryMiddleSize (0) {
   DEF_LOG ("Attachment::Attachment", "curPos: " << curPos << " level: " << level);
   readMime (mbox, curPos);
@@ -321,6 +323,9 @@ Attachment::readMime (ifstream &mbox, streamoff &curPos) {
   cid = getProp (contentIDToken, cidDefRegEx);
 
   if (caseInsensitiveFind (getContentType (), MULTIPART) != string::npos) {
+    string multiProp = getProp (contentTypeToken, multiRegEx);
+    if (SIGNED == multiProp)
+      isSigned = true;
     boundary = getProp (contentTypeToken, boundaryRegEx);
     removeQuote (boundary);
     LOG ("boundary: " << boundary);
@@ -416,18 +421,19 @@ Attachment::markDisclaim (bool &plainMarked, bool &htmlMarked) {
 
 // ================================================================================
 bool
-Attachment::markSignificant (const string &parentMultiProp, const streamoff &minAttachSize, ifstream &mbox, vector<Attachment *> &allMarkedPtrs) {
+Attachment::markSignificant (const string &parentMultiProp, const bool &parentSigned, const streamoff &minAttachSize, ifstream &mbox, vector<Attachment *> &allMarkedPtrs) {
   DEF_LOG ("Attachment::markSignificant", "parentMultiProp: " << parentMultiProp << " minAttachSize: " << minAttachSize);
+  isSigned |= parentSigned;
   string textProp = getProp (contentTypeToken, textRegEx);
   bool cantBeExtract ((parentMultiProp == ALTERNATIVE && (textProp == PLAIN || textProp == HTML)) ||
 		      (parentMultiProp == RELATED && textProp == HTML));
   string multiProp = getProp (contentTypeToken, multiRegEx);
   for (Attachment &sub : subAttachements)
-    cantBeExtract |= sub.markSignificant (multiProp, minAttachSize, mbox, allMarkedPtrs);
+    cantBeExtract |= sub.markSignificant (multiProp, parentSigned || isSigned, minAttachSize, mbox, allMarkedPtrs);
   if (getProp (contentTypeToken, textRegEx) == HTML) {
-    if (KAZ_ATTACH_NAME == getAttachName ()) {
+    if (KAZ_ATTACH_NAME == getAttachName ())
       isKazAttachment = true;
-    } else {
+    else {
       string content = getContent (mbox);
       vector<string> imgs;
       getSection (content, IMG_BEGIN, IMG_END, imgs);
@@ -438,16 +444,27 @@ Attachment::markSignificant (const string &parentMultiProp, const streamoff &min
   }
   cantBeExtract |= toUpdate;
   if (boundary.empty () && getSize () >= minAttachSize && !cantBeExtract)
-    cantBeExtract = toExtract = true; // XXX cantBeExtract ?
+    cantBeExtract = toExtract = true;
   if (toExtract || toUpdate || toDisclaim || isKazAttachment)
     allMarkedPtrs.push_back (this);
   return cantBeExtract;
 }
 
+// ================================================================================
+string
+Attachment::getMime (ifstream &mbox) const {
+  DEF_LOG ("Attachment::getMime", "beginPos: " << beginPos << " contentPos: " << contentPos);
+  string mime;
+  mime.resize (contentPos-beginPos);
+  mbox.seekg (beginPos, ios::beg);
+  mbox.read (&mime[0], contentPos-beginPos);
+  return mime;
+}
+
 // ================================================================================
 string
 Attachment::getContent (ifstream &mbox) const {
-  DEF_LOG ("Attachment::getContent", "contentPos: " << contentPos);
+  DEF_LOG ("Attachment::getContent", "contentPos: " << contentPos << " endPos: " << endPos);
   string content;
   content.resize (endPos-contentPos);
   mbox.seekg (contentPos, ios::beg);
@@ -505,7 +522,9 @@ Attachment::replaceEmbedded (string &content) const {
 ostream&
 kaz::operator << (ostream& os, const Attachment& attachment) {
   string prop, sep;
-  if (attachment.toExtract) { prop = "to extract"; sep = ", "; }
+  if (attachment.isSigned) { prop += sep+"signed"; sep = ", "; }
+  if (attachment.isKazAttachment) { prop += sep+"kazDisclaim"; sep = ", "; }
+  if (attachment.toExtract) { prop += sep+"to extract"; sep = ", "; }
   if (attachment.toUpdate) { prop += sep+"need update"; sep = ", "; }
   if (attachment.toDisclaim) { prop += sep+"need diclaim"; sep = ", "; }
   if (attachment.embeddedData.size ()) { prop += sep+"embeddedData"; }
diff --git a/src/cpp/MainAttachment.cpp b/src/cpp/MainAttachment.cpp
index 5338138..c534d45 100644
--- a/src/cpp/MainAttachment.cpp
+++ b/src/cpp/MainAttachment.cpp
@@ -177,8 +177,8 @@ MainAttachment::readArchiveUrl () {
   archiveDownloadURL.clear ();
   string line;
   getline (cin, line);
-  LOG_BUG (line.rfind ("arch: ", 0) != 0, return, "eMailShrinker: bug 9: no archive link. (line: " << line << ")");
-  LOG_BUG (line.rfind ("arch: bad", 0) == 0, return, "eMailShrinker: bug 10: bad archive link. (line: " << line << ")");
+  LOG_BUG (line.rfind ("arch: ", 0) != 0, return, "eMailShrinker: bug M9: no archive link. (line: " << line << ")");
+  LOG_BUG (line.rfind ("arch: bad", 0) == 0, return, "eMailShrinker: bug M10: bad archive link. (line: " << line << ")");
   if (line.rfind ("arch: none", 0) == 0)
     return;
   archiveDownloadURL = line.substr (6);
@@ -192,7 +192,7 @@ MainAttachment::readDownloadUrl (string &url) {
   string line;
   getline (cin, line);
   LOG ("get URL: " << line);
-  LOG_BUG (line.rfind ("url: ", 0) != 0, return, "eMailShrinker: bug 11: no download link. (line: " << line << ")");
+  LOG_BUG (line.rfind ("url: ", 0) != 0, return, "eMailShrinker: bug M11: no download link. (line: " << line << ")");
   url = line.substr (5);
 }
 
@@ -231,7 +231,7 @@ MainAttachment::getDisclaim (string &plain, string &html) const {
   int linkCount (0);
   string plainNewLinks, htmlNewLinks;
   for (Attachment *attachP : allMarkedPtrs) {
-    if (!attachP->toExtract)
+    if (attachP->isSigned || !attachP->toExtract)
       continue;
     addLink (plainNewLinks, htmlNewLinks, attachP->downloadUrl, attachP->getAttachName ());
     ++linkCount;
@@ -240,7 +240,7 @@ MainAttachment::getDisclaim (string &plain, string &html) const {
     //   previousLinks.erase (attachP->downloadUrl);
   }
   for (Attachment *attachP : allMarkedPtrs) {
-    if (!attachP->embeddedData.size ())
+    if (attachP->isSigned || !attachP->embeddedData.size ())
       continue;
     for (EmbeddedData &embedded : attachP->embeddedData) {
       addLink (plainNewLinks, htmlNewLinks, embedded.downloadUrl, embedded.name);
@@ -449,7 +449,7 @@ MainAttachment::markSignificant (const streamoff &minAttachSize, ifstream &mbox)
   bool plainMarked (false), htmlMarked (false);
   markDisclaim (plainMarked, htmlMarked);
   emptyEMail = ! (plainMarked || htmlMarked);
-  Attachment::markSignificant ("", minAttachSize, mbox, allMarkedPtrs);
+  Attachment::markSignificant ("", isSigned, minAttachSize, mbox, allMarkedPtrs);
 }
 
 // ================================================================================
@@ -492,7 +492,7 @@ MainAttachment::extract (ifstream &mbox, const SizeArg &minSize) const {
   int attachCount (0);
   string dirName, mediaName;
   for (Attachment *attachP : allMarkedPtrs) {
-    if (attachP->isKazAttachment || !attachP->toExtract)
+    if (attachP->isSigned || attachP->isKazAttachment || !attachP->toExtract)
       continue;
     newPjEntry (attachCount, attachP->getContentType (), attachP->getAttachName (), dirName, mediaName);
     ++attachCount;
@@ -543,7 +543,7 @@ MainAttachment::extract (ifstream &mbox, const SizeArg &minSize) const {
     cout << dirName << endl;
   }
   for (Attachment *attachP : allMarkedPtrs) {
-    if (!attachP->embeddedData.size ())
+    if (attachP->isSigned || !attachP->embeddedData.size ())
       continue;
     string content = attachP->getContent (mbox);
     vector<string> imgs;
@@ -575,7 +575,7 @@ MainAttachment::substitute (ifstream &mbox, ofstream &outbox, const SizeArg &min
   removePreviousArchive ();
   map<const string, const string> translateHtml;
   for (Attachment *attachP : allMarkedPtrs)
-    if (attachP->toExtract && !attachP->isKazAttachment) {
+    if (!attachP->isSigned && attachP->toExtract && !attachP->isKazAttachment) {
       readDownloadUrl (attachP->downloadUrl);
       if (attachP->downloadUrl.empty ()) {
 	LOG ("no change");
@@ -589,7 +589,7 @@ MainAttachment::substitute (ifstream &mbox, ofstream &outbox, const SizeArg &min
       }
     }
   for (Attachment *attachP : allMarkedPtrs) {
-    if (!attachP->embeddedData.size ())
+    if (attachP->isSigned || !attachP->embeddedData.size ())
       continue;
     for (EmbeddedData &embedded : attachP->embeddedData)
       readDownloadUrl (embedded.downloadUrl);
@@ -601,11 +601,32 @@ MainAttachment::substitute (ifstream &mbox, ofstream &outbox, const SizeArg &min
   getDisclaim (plainDisclaim, htmlDisclaim);
 
   // copy email
-  streamoff curPos = 0;
-  if (boundary.empty () && plainDisclaim.size () && (attachMode & ATTACHMENT)) {
-    // XXX if no multipart ?
-    LOG_BUG (true, /* */, "eMailShrinker: bug 12: not multipart.");
+  if (plainDisclaim.size () && emptyEMail && boundary.empty ()) {
+    // only one attachment must be replace
+    cerr << "eMailShrinker: force one attachment" << endl;
+    string mime (getMime (mbox));
+    string::size_type startPos = (0);
+    for (string token : {string ("Content-Transfer-Encoding"), Attachment::contentTypeToken}) {
+      startPos = caseInsensitiveFind (mime, "Content-Transfer-Encoding");
+      for (string::size_type stopPos (startPos);
+	   (stopPos = mime.find ("\n", stopPos)) != string::npos;
+	   ) {
+	if (string (" \t").find (mime [stopPos+1]) == string::npos) {
+	  mime.erase (startPos, stopPos-startPos);
+	  break;
+	}
+      }
+    }
+    mime.insert (startPos, KAZ_EMPTY_TEXT_PLAIN);
+    string content (plainDisclaim);
+    base64Encode (content);
+    outbox << mime
+	   << content << endl;
+    outbox.flush ();
+    outbox.close ();
+    return;
   }
+  streamoff curPos = 0;
   copy (mbox, outbox, curPos, contentPos);
   curPos = contentPos;
 
@@ -626,9 +647,12 @@ MainAttachment::substitute (ifstream &mbox, ofstream &outbox, const SizeArg &min
     copy (mbox, outbox, curPos, attachP->beginInParent);
     LOG_BUG (attachP->toUpdate && attachP->toExtract, /**/, "eMailShrinker: bug M5: update and extract. pos: " << attachP->beginPos);
 
-    if (attachP->toExtract || attachP->isKazAttachment) {
-      LOG ("skip Extracted or previous attachments");
+    if (attachP->isSigned) {
+      LOG ("don't change signed content");
+      copy (mbox, outbox, attachP->beginInParent, attachP->endPos);
       
+    } else if (attachP->toExtract || attachP->isKazAttachment) {
+      LOG ("skip Extracted or previous attachments");
 
     } else if (attachP->toUpdate) {
       string textProp = attachP->getProp (contentTypeToken, textRegEx);
@@ -718,7 +742,7 @@ MainAttachment::substitute (ifstream &mbox, ofstream &outbox, const SizeArg &min
     outbox.flush ();
   }
   copy (mbox, outbox, curPos, endPos);
-  outbox << endl;
+  //outbox << endl;
   outbox.close ();
 }
 
diff --git a/src/cpp/eMailShrinker.cpp b/src/cpp/eMailShrinker.cpp
index 1af815e..9165e9b 100644
--- a/src/cpp/eMailShrinker.cpp
+++ b/src/cpp/eMailShrinker.cpp
@@ -33,8 +33,8 @@
 ////////////////////////////////////////////////////////////////////////////
 
 #include "version.hpp"
-const std::string kaz::LAST_VERSION_NUM ("2.7");
-const std::string kaz::LAST_VERSION_DATE ("2022-12-19");
+const std::string kaz::LAST_VERSION_NUM ("2.8");
+const std::string kaz::LAST_VERSION_DATE ("2022-12-23");
 const std::string kaz::LAST_VERSION (LAST_VERSION_NUM+" "+LAST_VERSION_DATE+" eMailShrinker");
 
 #include <iostream>
diff --git a/src/cpp/kazMisc.cpp b/src/cpp/kazMisc.cpp
index ae31a52..d0cf270 100644
--- a/src/cpp/kazMisc.cpp
+++ b/src/cpp/kazMisc.cpp
@@ -259,17 +259,22 @@ kaz::base64Decode (string &content) {
   LOG ("len: " << len);
   unsigned char buff[4];
   int idx = 0;
-  string::iterator p (content.begin ()), q (p);
+  string::iterator p (content.begin ()), q (p), lastOK (p);
   for (;
        p < content.end ();
        ++p) {
     char c = *p;
     if (c == '=')
       break;
-    if (c == '\n')
+    if (c == '\n') {
+      lastOK = p;
       continue;
+    }
 
-    LOG_BUG (!isBase64 (c), return, "kazMisc::base64Decode bug: bad base64 format. (content: " << content << ")");
+    if (isBase64 (c)) {
+      content.resize (lastOK-content.begin ());
+      LOG ("kazMisc::base64Decode bug: bad base64 format. (content: " << content << ")");
+    }
     buff [idx] = getBase64Val (c);
     if (++idx != 4)
       continue;
diff --git a/src/include/Attachment.hpp b/src/include/Attachment.hpp
index 595d097..758b009 100644
--- a/src/include/Attachment.hpp
+++ b/src/include/Attachment.hpp
@@ -54,7 +54,7 @@ namespace kaz {
     //static const vector<const string> stringsToUpdate;
     static vector<string> stringsToUpdate;
     /*! mime tokens */
-    static const string contentTypeToken, contentDispositionToken, contentTransferEncodingToken, base64Token, quotedPrintableToken, contentIDToken, PLAIN, HTML, RELATED, ALTERNATIVE, KAZ_ATTACH_NAME;
+    static const string contentTypeToken, contentDispositionToken, contentTransferEncodingToken, base64Token, quotedPrintableToken, contentIDToken, PLAIN, HTML, MULTIPART, RELATED, ALTERNATIVE, SIGNED, KAZ_ATTACH_NAME;
     /*! pattern to extract mime values */
     static const regex nameRegEx, nameCharsetRegEx, boundaryRegEx, cidDefRegEx, textRegEx, multiRegEx;
 
@@ -100,7 +100,7 @@ namespace kaz {
     /*! char position of attachment content */
     streamoff contentPos, endPos;
     /*! properties of the attachment */
-    bool toExtract, toUpdate, toDisclaim, isKazAttachment;
+    bool toExtract, toUpdate, toDisclaim, isKazAttachment, isSigned;
     /*! id of an image embedded in mbox */
     string cid;
     /*! url to replace the attachment */
@@ -131,7 +131,9 @@ namespace kaz {
     /*! recursively marks alternative attachments to be disclaim */
     void markDisclaim (bool &plainMarked, bool &htmlMarked);
     /*! recursively marks big attachments to be removed and upated (including disclaim). return true when part need to be updated (can't be extracted). */
-    bool markSignificant (const string &parentMultiProp, const streamoff &minAttachSize, ifstream &mbox, vector<Attachment *> &allMarkedPtrs);
+    bool markSignificant (const string &parentMultiProp, const bool &parentSigned, const streamoff &minAttachSize, ifstream &mbox, vector<Attachment *> &allMarkedPtrs);
+    /*! get a copy of mime header */
+    string getMime (ifstream &mbox) const;
     /*! get a copy of the content. Base64 is decoded. Quoted-Printable is unwarp and unquoted */
     string getContent (ifstream &mbox) const;
     /*! write the content, encoded if necessary (base64 and quoted-printable) */