Accumulo is not designed to run under Windows. Nor are its unit tests. However, if you persist in this foolishness, add the following elements to the indicated pom.xml files. 
core/pom.xml

    <profile>
        <id>skipped_tests_on_windows</id>
        <activation>
            <activeByDefault>false</activeByDefault>
            <os>
                <family>Windows</family>
            </os>
            </activation>
        <build>
        <plugins>
            <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-surefire-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>**/AccumuloFileOutputFormatTest.java</exclude>
                        <exclude>**/AccumuloFileInputFormatTest.java</exclude>
                        <exclude>**/AccumuloOutputFormatTest.java</exclude>
                        <exclude>**/AccumuloRowInputFormatTest.java</exclude>
                        <exclude>**/AccumuloInputFormatTest.java</exclude>
                        <exclude>**/MockTableOperationsTest.java</exclude>
                        <exclude>**/AggregatingIteratorTest.java</exclude>
                        <exclude>**/IterUtilTest.java</exclude>
                        <exclude>**/CombinerTest.java</exclude>
                        <exclude>**/FormatterCommandTest.java</exclude>
                        </excludes>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    </profile>

examples/simple/pom.xml

    <profile>
        <id>skipped_tests_on_windows</id>
        <activation>
            <activeByDefault>false</activeByDefault>
            <os>
                <family>Windows</family>
            </os>
            </activation>
        <build>
            <plugins>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-surefire-plugin</artifactId>
                    <configuration>
                        <excludes>
                            <exclude>**/ChunkInputFormatTest.java</exclude>
                            </excludes>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    </profile>

proxy/pom.xml

    <profile>
        <id>skipped_tests_on_windows</id>
        <activation>
            <activeByDefault>false</activeByDefault>
            <os>
                <family>Windows</family>
            </os>
            </activation>
        <build>
            <plugins>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-surefire-plugin</artifactId>
                    <configuration>
                        <excludes>
                            <exclude>**/SimpleTest.java</exclude>
                            <exclude>**/TestProxyInstanceOperations.java</exclude>
                        </excludes>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    </profile>
  </profiles>

server/pom.xml

    <profile>
        <id>skipped_tests_on_windows</id>
        <activation>
            <activeByDefault>false</activeByDefault>
            <os>
                <family>Windows</family>
            </os>
            </activation>
        <build>
            <plugins>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-surefire-plugin</artifactId>
                    <configuration>
                        <excludes>
                            <exclude>**/TableLoadBalancerTest.java</exclude>
                            </excludes>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    </profile>

start/pom.xml

    <profile>
        <id>skipped_tests_on_windows</id>
        <activation>
            <activeByDefault>false</activeByDefault>
            <os>
                <family>Windows</family>
            </os>
            </activation>
        <build>
        <plugins>
            <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-surefire-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>**/AccumuloVFSClassLoaderTest.java</exclude>
                        <exclude>**/ReadOnlyHdfsFileProviderTest.java</exclude>
                        <exclude>**/VfsClassLoaderTest.java</exclude>
                        </excludes>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    </profile>

test/pom.xml

    <profile>
        <id>skipped_tests_on_windows</id>
        <activation>
            <activeByDefault>false</activeByDefault>
            <os>
                <family>Windows</family>
            </os>
            </activation>
        <build>
            <plugins>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-surefire-plugin</artifactId>
                    <configuration>
                        <excludes>
                            <exclude>**/MiniAccumuloClusterTest.java</exclude>
                            <exclude>**/ShellServerTest.java</exclude>
                        </excludes>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    </profile>