If you are using Internet Explorer 6.0 on Windows XP or Windows 2000 you may experience very long delays when uploading your data to our servers. This may cause a subsequent timeout error which will mean that your upload will fail.
Our testing indicates file uploads take 30 times as long as they should.
Unfortunately this is a browser issue and there is nothing we can apply to our servers that will resolve this problem.
Microsoft have identified this as a bug in Internet Explorer 6.0 running on Windows XP or Windows 2000; Microsoft Knowledge Base article 840139 has further details and information on how to obtain their hotfix. We have applied this hotfix to affected systems at HESA and it does resolve this issue. This fix is stated as being in cumulative security update MS05-025 however our testing indicates that it is not and after applying that update the same very long upload times have reappeared. Applying subsequent cumulative security updates MS05-038 and MS05-052 does not help either. Our assumption is that this hotfix did not actually make it into the released version of wininet.dll.
Use another browser; we have never experienced this issue with Mozilla Firefox.
Microsoft have registry edit workaround detailed in KB329781; it works for us.