Transferred files generate Runtime Error

I have transferred files in SFTP mode and all now generate a runtime error:
Line: 0
Error: Object expected
This is my first time using WinSCP. I have tried different settings without success. Thanks for any help.

gas wrote:

Line: 0
Error: Object expected

Where do you see this message? It looks like Explorer's JavaScript error message :-)

Yes it is an Explorer message but the error occurs in every browser. In Opera, for example, the Javascript error reads:
JavaScript -
Event thread: load
Error:
name: ReferenceError
message: Statement on line 1: Undefined variable: MM_preloadImages
Backtrace:
Line 1 of function script etc etc....

The files on the web site were running without errors before this. To make sure I hadn't done something to the code without knowing it, I did a test where I sftp'd an error-free file, renamed it and sent it back and it now has an error. Something is happening during the transfer.

martin wrote:

Where do you see this message? It looks like Explorer's JavaScript error message :-)

Sorry, but you game me no clue what are you actually doing. What has Javascript in web browser to do with WinSCP...