This rule set detects calls that are likely to cause runtime exceptions on IQueryable types. To add this rule set do: Resharper->Options->Custom Patterns ->Import

QueryableResharperRules.xml

<CustomPatterns>
  <Pattern Severity="ERROR" FormatAfterReplace="True" ShortenReferences="True" Language="CSHARP">
    <Comment>FirstOrDefault not supported by all Queryable Types</Comment>
    <ReplaceComment>Convert to supported version</ReplaceComment>
    <ReplacePattern>$q$.Where($x$).FirstOrDefault()</ReplacePattern>
    <SearchPattern>$q$.FirstOrDefault($x$)</SearchPattern>
    <Params />
    <Placeholders>
      <ExpressionPlaceholder Name="q" ExpressionType="System.Linq.IQueryable" ExactType="False" />
      <ArgumentPlaceholder Name="x" Minimal="1" Maximal="-1" />
    </Placeholders>
  </Pattern>
  <Pattern Severity="ERROR" FormatAfterReplace="True" ShortenReferences="True" Language="CSHARP">
    <Comment>First not supported by all Queryable Types</Comment>
    <ReplaceComment>Convert to supported version</ReplaceComment>
    <ReplacePattern>$q$.Where($x$).First()</ReplacePattern>
    <SearchPattern>$q$.First($x$)</SearchPattern>
    <Params />
    <Placeholders>
      <ExpressionPlaceholder Name="q" ExpressionType="System.Linq.IQueryable" ExactType="False" />
      <ArgumentPlaceholder Name="x" Minimal="1" Maximal="-1" />
    </Placeholders>
  </Pattern>
  <Pattern Severity="ERROR" FormatAfterReplace="True" ShortenReferences="True" Language="CSHARP">
    <Comment>Single not supported by all Queryable Types</Comment>
    <ReplaceComment>Convert to supported version</ReplaceComment>
    <ReplacePattern>$q$.Where($x$).Single()</ReplacePattern>
    <SearchPattern>$q$.Single($x$)</SearchPattern>
    <Params />
    <Placeholders>
      <ExpressionPlaceholder Name="q" ExpressionType="System.Linq.IQueryable" ExactType="False" />
      <ArgumentPlaceholder Name="x" Minimal="1" Maximal="-1" />
    </Placeholders>
  </Pattern>
  <Pattern Severity="ERROR" FormatAfterReplace="True" ShortenReferences="True" Language="CSHARP">
    <Comment>SingleOrDefault not supported by all Queryable Types</Comment>
    <ReplaceComment>Convert to supported version</ReplaceComment>
    <ReplacePattern>$q$.Where($x$).SingleOrDefault()</ReplacePattern>
    <SearchPattern>$q$.SingleOrDefault($x$)</SearchPattern>
    <Params />
    <Placeholders>
      <ExpressionPlaceholder Name="q" ExpressionType="System.Linq.IQueryable" ExactType="False" />
      <ArgumentPlaceholder Name="x" Minimal="1" Maximal="-1" />
    </Placeholders>
  </Pattern>
  <Pattern Severity="ERROR" FormatAfterReplace="True" ShortenReferences="True" Language="CSHARP">
    <Comment>Any not supported by all Queryable Types</Comment>
    <ReplaceComment>Convert to supported version</ReplaceComment>
    <ReplacePattern>$q$.Where($x$).Any()</ReplacePattern>
    <SearchPattern>$q$.Any($x$)</SearchPattern>
    <Params />
    <Placeholders>
      <ExpressionPlaceholder Name="q" ExpressionType="System.Linq.IQueryable" ExactType="False" />
      <ArgumentPlaceholder Name="x" Minimal="1" Maximal="-1" />
    </Placeholders>
  </Pattern>
  <Pattern Severity="ERROR" FormatAfterReplace="True" ShortenReferences="True" Language="CSHARP">
    <Comment>All not supported by all Queryable Types</Comment>
    <ReplaceComment>Convert to supported version</ReplaceComment>
    <ReplacePattern>$q$.Where($x$).All()</ReplacePattern>
    <SearchPattern>$q$.All($x$)</SearchPattern>
    <Params />
    <Placeholders>
      <ExpressionPlaceholder Name="q" ExpressionType="System.Linq.IQueryable" ExactType="False" />
      <ArgumentPlaceholder Name="x" Minimal="1" Maximal="-1" />
    </Placeholders>
  </Pattern>
</CustomPatterns>