robots.txt errors in sitemap area

[tihami]

hi members,
i am working on landscaping website
Target area for ottawa Canada
website built in custom php
Total website pages are 26

my webmaster shows the robots.txt error in sitemap area

Error Type: Warnings
Issue: Url Blocked by robots.txt
Description: Sitemap contains urls which are blocked by robots.txt

last day i upload the following code on robots.txt

User-Agent: *
Disallow:

currently i upload the blank robots.txt file.

but still there are 26 error shows in sitemap area.
can you please help me to resolve this issue.

[phranque]

have you tried "fetch as googlebot" in GWT?

[lucy24]

but still there are 26 error

Information in GWT doesn't update in real time. You should expect messages about problems going back several months.

Webmaster Tools (anywhere, not just Google) can be a useful feature. But don't think of it as a direct pipeline into the search engine's database. It's only a direct pipeline into, well, Webmaster Tools.