diff --git a/.DS_Store b/.DS_Store
index e16a5bf..56aebf0 100644
Binary files a/.DS_Store and b/.DS_Store differ
diff --git a/encrypted.bin b/encrypted.bin
deleted file mode 100644
index f9a52bf..0000000
--- a/encrypted.bin
+++ /dev/null
@@ -1 +0,0 @@
-Salted__P@
;íûÖÇXzq2Uz8tøT|¹KùÉu
\ No newline at end of file
diff --git a/unit05_key_exchange/lecture/~$unit05_key_exchange.pptx b/unit05_key_exchange/lecture/~$unit05_key_exchange.pptx
deleted file mode 100644
index b71c76f..0000000
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diff --git a/unit06_trust_dig_cert/.DS_Store b/unit06_trust_dig_cert/.DS_Store
new file mode 100644
index 0000000..1ae4f49
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diff --git a/unit06_trust_dig_cert/lecture/.DS_Store b/unit06_trust_dig_cert/lecture/.DS_Store
new file mode 100644
index 0000000..5008ddf
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diff --git a/unit06_trust_dig_cert/lecture/unit06_digital_cert.key b/unit06_trust_dig_cert/lecture/unit06_digital_cert.key
deleted file mode 100755
index fb2beab..0000000
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diff --git a/unit06_trust_dig_cert/lecture/unit06_digital_cert.pptx b/unit06_trust_dig_cert/lecture/unit06_digital_cert.pptx
index 5d6a80b..10fdb49 100644
Binary files a/unit06_trust_dig_cert/lecture/unit06_digital_cert.pptx and b/unit06_trust_dig_cert/lecture/unit06_digital_cert.pptx differ