First of all, I have moved the topic to Trados Support - please use this forum to post Trados-related topics.
Which (underlying) file type was the TTX file created from?
Though Trados seems to have cleaned file, when I open it no changes have taken place, both source and target are there.
That would be expected behaviour, as a cleanup of a TTX file creates the target file, but leaves the TTX unchanged (essentially, the TTX file is equivalent to a .bak file when working on Word documents).
Also, I have tried saving target. Everything seems ok, but whan I try to open the file a message reads:
35017 Expected end of tag "xref"
Searching the Trados KB for the error number comes up with Article 1389 - can you check the source file for authoring errors?