IIS 7 dynamic compression truncates downloaded files

I have a problem with an ASP.NET application that has recently been ported to a new server with IIS7 instead of IIS6. The application has been upgraded to .NET4, although most of the code remains because it was originally written in .NET 1.1. The application manages the company's static tables, and the user can load any static table data into CSV or XML from a web page.

Problem. If IIS7's Enable Dynamic Content Compression feature is enabled, the file is corrupted (the end of the file is truncated). Corruption seems NOT accidental, i.e. I always get the same result as long as the input is equal. For different sets of input data, the effect size (the number of characters cut off) also varies. When I turn off dynamic compression, the problem completely disappears.

Download examples (I always send only the last line of the entire CSV file):

• static table A

  • dynamic compression (full file length 720 bytes):

    2010-10-21 00:00:00;;"P ";"registrované partnerství";"REGISTERED PARNTERSHIP";"registrované partnerstvo";0
    

  • dynamic compression is turned off (the last 1 byte is truncated - that is, the last line break has lost its "LF" char), file length = 719 bytes):

• static table B

  • dynamic compression off (no distortion, file length = 593349 bytes):

    2012-04-16 00:00:00;;"800650";"Finanční centrum Třebíč";"PSB FC Třebíč";"PSB FC Třebíč";"PSB FC Třebíč";9;2;61;"67401";"Třebíč";"Karlovo náměstí 32/26";5057;2518;852;;;2012-05-02 00:00:00;0
    

  • ( 2 (.. CRLF ), = 593347 ):

• C

  • ( , = 282 ):

    2012-04-16 00:00:00;;"3";"Zaslat do vlastních rukou";0
    

  • ( 5 , = 275 ):

    2012-04-16 00:00:00;;"3";"Zaslat do vlastních ruk
    

• D

  • ( , = 6506 ):

    2010-02-20 00:00:00;2010-03-20 00:00:00;390;"879001";2;0
    

  • ( 13 , = 6491 ):

    2010-02-20 00:00:00;2010-03-20 00:00:00;390
    

XML, - XML ​​ 1 . :

</Export>

</Export

. , . , , , , , CSV XML: